diff --git a/app/api/friend.py b/app/api/friend.py
new file mode 100644
index 0000000..fecce43
--- /dev/null
+++ b/app/api/friend.py
@@ -0,0 +1,80 @@
+from fastapi import APIRouter, Depends, HTTPException
+from sqlalchemy.orm import Session
+from app.core.deps import get_db, get_current_user
+from app.schemas.friend import FriendRequestCreate, FriendRequestResponse, FriendResponse
+from app.schemas.character import CharacterResponse
+from app.services import friend_service
+from app.models.user import User
+
+router = APIRouter()
+
+
+@router.post("/request", response_model=FriendRequestResponse)
+def send_request(
+    request_data: FriendRequestCreate,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    return friend_service.send_friend_request(db, current_user.id, request_data.to_user_email)
+
+
+@router.get("/requests/received", response_model=list[FriendRequestResponse])
+def get_received_requests(
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    return friend_service.get_received_requests(db, current_user.id)
+
+
+@router.get("/requests/sent", response_model=list[FriendRequestResponse])
+def get_sent_requests(
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    return friend_service.get_sent_requests(db, current_user.id)
+
+
+@router.post("/requests/{request_id}/cancel")
+def cancel_sent_request(
+    request_id: int,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    friend_service.cancel_sent_request(db, request_id, current_user.id)
+    return {"detail": "요청을 취소했습니다."}
+
+
+@router.post("/requests/{request_id}/respond")
+def respond_to_request(
+    request_id: int,
+    accept: bool,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    friend_service.respond_to_request(db, request_id, current_user.id, accept)
+    return {"detail": "요청을 처리했습니다."}
+
+
+@router.get("/list", response_model=list[int])
+def get_friend_list(
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    return friend_service.get_friend_list(db, current_user.id)
+
+@router.get("/{friend_id}/characters", response_model=list[CharacterResponse])
+def get_friend_characters(
+    friend_id: int,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    return friend_service.get_public_characters_of_friend(db, current_user.id, friend_id)
+
+@router.delete("/{friend_id}")
+def delete_friend(
+    friend_id: int,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user)
+):
+    friend_service.delete_friend(db, current_user.id, friend_id)
+    return {"detail": "친구가 삭제되었습니다."}
diff --git a/app/api/user.py b/app/api/user.py
index 68c5084..387dee4 100644
--- a/app/api/user.py
+++ b/app/api/user.py
@@ -1,16 +1,17 @@
 # app/api/user.py
 
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, status, Query
 from fastapi.logger import logger
 import traceback
 import sys
 from sqlalchemy.orm import Session
-from app.schemas.user import UserCreate, UserResponse, PasswordUpdateRequest
+from app.schemas.user import UserCreate, UserResponse, PasswordUpdateRequest, UserPublicInfoResponse, UserByCharacterResponse
 from app.crud.user import create_user
 from app.models.user import User
 from app.core.database import SessionLocal
 from app.core.deps import get_current_user
 from app.core.security import verify_password, get_password_hash
+from app.services import user_service
 
 router = APIRouter()
 
@@ -56,4 +57,20 @@ def update_password(
     except Exception as e:
         logger.error(f"❌ 비밀번호 변경 중 예외 발생: {e}")
         traceback.print_exc(file=sys.stdout)  # ← 여기가 핵심
-        raise
\ No newline at end of file
+        raise
+
+@router.get("/public-info", response_model=UserPublicInfoResponse)
+def get_public_info(
+        email: str = Query(...),
+        db: Session = Depends(get_db),
+        current_user: User = Depends(get_current_user)
+):
+    return user_service.get_user_public_info(db, current_user.id, email)
+
+@router.get("/by-character", response_model=UserByCharacterResponse)
+def get_by_character(
+    server: str,
+    name: str,
+    db: Session = Depends(get_db)
+):
+    return user_service.get_user_by_character(db, server, name)
\ No newline at end of file
diff --git a/app/main.py b/app/main.py
index 74e480c..005e751 100644
--- a/app/main.py
+++ b/app/main.py
@@ -6,38 +6,39 @@ from app.core.deps import get_current_user
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.security import OAuth2PasswordBearer
 import traceback
+from app.models import user, friend, character, homework
 
-from app.api import user, auth, character, homework, character_homework, dashboard
+from app.api import user, auth, character, homework, character_homework, dashboard, friend
 
 oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/auth/login")
 
-# app = FastAPI(
-#     title="숙제노기 API",
-#     description="마비노기 모바일 숙제 관리용 백엔드 API",
-#     version="0.1.0",
-#     docs_url="/docs",
-#     redoc_url=None,
-#     openapi_url="/openapi.json",
-#     root_path="/api"
-# )
-
 app = FastAPI(
-    docs_url=None,
+    title="숙제노기 API",
+    description="마비노기 모바일 숙제 관리용 백엔드 API",
+    version="0.1.0",
+    docs_url="/docs",
     redoc_url=None,
-    openapi_url=None
+    openapi_url="/openapi.json",
+    root_path="/api"
 )
 
-@app.get("/docs", include_in_schema=False)
-def custom_docs(user=Depends(get_current_user)):
-    return get_swagger_ui_html(openapi_url="/openapi.json", title="Sukjenogi API Docs")
-
-@app.get("/openapi.json", include_in_schema=False)
-def custom_openapi(user=Depends(get_current_user)):
-    return get_openapi(
-        title="Sukjenogi API",
-        version="0.2",
-        routes=app.routes
-    )
+# app = FastAPI(
+#     docs_url=None,
+#     redoc_url=None,
+#     openapi_url=None
+# )
+#
+# @app.get("/docs", include_in_schema=False)
+# def custom_docs(user=Depends(get_current_user)):
+#     return get_swagger_ui_html(openapi_url="/openapi.json", title="Sukjenogi API Docs")
+#
+# @app.get("/openapi.json", include_in_schema=False)
+# def custom_openapi(user=Depends(get_current_user)):
+#     return get_openapi(
+#         title="Sukjenogi API",
+#         version="0.2",
+#         routes=app.routes
+#     )
 
 @app.middleware("http")
 async def log_exceptions_middleware(request: Request, call_next):
@@ -57,7 +58,8 @@ origins = [
 
 app.add_middleware(
     CORSMiddleware,
-    allow_origins=origins,
+    # allow_origins=origins,
+    allow_origins=["*"],
     allow_credentials=True,
     allow_methods=["*"],
     allow_headers=["*"],
@@ -69,6 +71,7 @@ app.include_router(character.router, prefix="/characters", tags=["Characters"])
 app.include_router(homework.router, prefix="/homeworks", tags=["Homeworks"])
 app.include_router(character_homework.router, prefix="/characterHomework", tags=["Character Homeworks"])
 app.include_router(dashboard.router, prefix="/dashboard", tags=["Dashboard"])
+app.include_router(friend.router, prefix="/friends", tags=["Friends"])
 
 @app.get("/")
 def read_root():
diff --git a/app/models/character.py b/app/models/character.py
index 193b175..cbe3475 100644
--- a/app/models/character.py
+++ b/app/models/character.py
@@ -22,6 +22,8 @@ class Character(Base):
 
     order = Column(Integer, default=0)
 
+    is_public = Column(Boolean, default=False, nullable=False)
+
 
 class CharacterHomework(Base):
     __tablename__ = "character_homeworks"
diff --git a/app/models/friend.py b/app/models/friend.py
new file mode 100644
index 0000000..bc8ef4d
--- /dev/null
+++ b/app/models/friend.py
@@ -0,0 +1,43 @@
+from sqlalchemy import Column, Integer, Enum, ForeignKey, DateTime, CheckConstraint, UniqueConstraint
+from sqlalchemy.orm import relationship
+from datetime import datetime
+from app.core.database import Base
+import enum
+from app.models.user import User
+
+class FriendRequestStatus(enum.Enum):
+    pending = "pending"
+    accepted = "accepted"
+    rejected = "rejected"
+    cancelled = "cancelled"
+
+
+class FriendRequest(Base):
+    __tablename__ = "friend_requests"
+
+    id = Column(Integer, primary_key=True, index=True)
+    from_user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
+    to_user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
+    status = Column(Enum(FriendRequestStatus), default=FriendRequestStatus.pending, nullable=False)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    updated_at = Column(DateTime, default=datetime.utcnow)
+
+    from_user = relationship(User, foreign_keys=[from_user_id])
+    to_user = relationship(User, foreign_keys=[to_user_id])
+
+
+class Friend(Base):
+    __tablename__ = "friends"
+
+    id = Column(Integer, primary_key=True, index=True)
+    user_id_1 = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
+    user_id_2 = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+    __table_args__ = (
+        UniqueConstraint("user_id_1", "user_id_2", name="unique_friend_pair"),
+        CheckConstraint("user_id_1 < user_id_2", name="check_user_order"),
+    )
+
+    user1 = relationship(User, foreign_keys=[user_id_1])
+    user2 = relationship(User, foreign_keys=[user_id_2])
diff --git a/app/models/homework.py b/app/models/homework.py
index e8506b6..0392317 100644
--- a/app/models/homework.py
+++ b/app/models/homework.py
@@ -1,4 +1,4 @@
-from sqlalchemy import Column, Integer, String, Time, ForeignKey, DateTime
+from sqlalchemy import Column, Integer, String, Time, ForeignKey, DateTime, Boolean
 from sqlalchemy.orm import relationship
 from datetime import time, datetime
 
@@ -20,3 +20,5 @@ class HomeworkType(Base):
     assigned_characters = relationship("CharacterHomework", back_populates="homework_type", cascade="all, delete")
 
     order = Column(Integer, default=0)
+
+    is_public = Column(Boolean, default=False, nullable=False)
diff --git a/app/models/user.py b/app/models/user.py
index 8e1984f..fe4e0e9 100644
--- a/app/models/user.py
+++ b/app/models/user.py
@@ -1,4 +1,5 @@
 # app/models/user.py
+from pydantic import BaseModel
 from sqlalchemy import Column, Integer, String, DateTime
 from sqlalchemy.orm import relationship
 from sqlalchemy.sql import func
@@ -15,4 +16,4 @@ class User(Base):
     updated_at = Column(DateTime, server_default=func.now(), onupdate=func.now(), nullable=False)
 
     characters = relationship("Character", back_populates="user")
-    homework_types = relationship("HomeworkType", back_populates="user", cascade="all, delete")
+    homework_types = relationship("HomeworkType", back_populates="user", cascade="all, delete")
\ No newline at end of file
diff --git a/app/schemas/friend.py b/app/schemas/friend.py
new file mode 100644
index 0000000..59b90b7
--- /dev/null
+++ b/app/schemas/friend.py
@@ -0,0 +1,36 @@
+from pydantic import BaseModel
+from datetime import datetime
+from enum import Enum
+
+
+class FriendRequestStatus(str, Enum):
+    pending = "pending"
+    accepted = "accepted"
+    rejected = "rejected"
+    cancelled = "cancelled"
+
+
+class FriendRequestCreate(BaseModel):
+    to_user_email: str
+
+
+class FriendRequestResponse(BaseModel):
+    id: int
+    from_user_id: int
+    to_user_id: int
+    status: FriendRequestStatus
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        orm_mode = True
+
+
+class FriendResponse(BaseModel):
+    id: int
+    user_id_1: int
+    user_id_2: int
+    created_at: datetime
+
+    class Config:
+        orm_mode = True
diff --git a/app/schemas/user.py b/app/schemas/user.py
index 1b5605b..86e2f99 100644
--- a/app/schemas/user.py
+++ b/app/schemas/user.py
@@ -20,3 +20,19 @@ class PasswordUpdateRequest(BaseModel):
 
     class Config:
         orm_mode = True
+
+
+class UserPublicInfoResponse(BaseModel):
+    id: int
+    email: str
+    is_friend: bool
+    request_sent: bool
+    request_received: bool
+
+class UserByCharacterResponse(BaseModel):
+    user_id: int
+    email: str
+    character_id: int
+    character_name: str
+    server: str
+    is_public: bool
\ No newline at end of file
diff --git a/app/services/friend_service.py b/app/services/friend_service.py
new file mode 100644
index 0000000..466c663
--- /dev/null
+++ b/app/services/friend_service.py
@@ -0,0 +1,174 @@
+from sqlalchemy.orm import Session
+from app.models.friend import FriendRequest, Friend, FriendRequestStatus
+from app.models.user import User
+from app.models.character import Character, CharacterHomework
+from app.models.homework import HomeworkType
+from fastapi import HTTPException, status
+from datetime import datetime
+
+
+def send_friend_request(db: Session, from_user_id: int, to_user_email: str):
+    to_user = db.query(User).filter(User.email == to_user_email).first()
+    if not to_user:
+        raise HTTPException(status_code=404, detail="해당 이메일의 유저를 찾을 수 없습니다.")
+
+    if to_user.id == from_user_id:
+        raise HTTPException(status_code=400, detail="자기 자신에게 친구 요청을 보낼 수 없습니다.")
+
+    # 이미 친구인지 확인
+    user_ids = sorted([from_user_id, to_user.id])
+    existing_friend = db.query(Friend).filter(
+        Friend.user_id_1 == user_ids[0],
+        Friend.user_id_2 == user_ids[1]
+    ).first()
+    if existing_friend:
+        raise HTTPException(status_code=400, detail="이미 친구 상태입니다.")
+
+    # 이미 pending 요청이 있는지 확인
+    existing_request = db.query(FriendRequest).filter(
+        FriendRequest.from_user_id == from_user_id,
+        FriendRequest.to_user_id == to_user.id,
+        FriendRequest.status == FriendRequestStatus.pending
+    ).first()
+    if existing_request:
+        raise HTTPException(status_code=400, detail="이미 친구 요청을 보낸 상태입니다.")
+
+    friend_request = FriendRequest(
+        from_user_id=from_user_id,
+        to_user_id=to_user.id,
+    )
+    db.add(friend_request)
+    db.commit()
+    db.refresh(friend_request)
+    return friend_request
+
+
+def get_received_requests(db: Session, user_id: int):
+    return db.query(FriendRequest).filter(
+        FriendRequest.to_user_id == user_id,
+        FriendRequest.status == FriendRequestStatus.pending
+    ).all()
+
+
+def get_sent_requests(db: Session, user_id: int):
+    return db.query(FriendRequest).filter(
+        FriendRequest.from_user_id == user_id,
+        FriendRequest.status == FriendRequestStatus.pending
+    ).all()
+
+
+def cancel_sent_request(db: Session, request_id: int, user_id: int):
+    request = db.query(FriendRequest).filter(
+        FriendRequest.id == request_id,
+        FriendRequest.from_user_id == user_id
+    ).first()
+
+    if not request:
+        raise HTTPException(status_code=404, detail="요청을 찾을 수 없습니다.")
+
+    request.status = FriendRequestStatus.cancelled
+    request.updated_at = datetime.utcnow()
+    db.commit()
+
+
+def respond_to_request(db: Session, request_id: int, user_id: int, accept: bool):
+    request = db.query(FriendRequest).filter(
+        FriendRequest.id == request_id,
+        FriendRequest.to_user_id == user_id,
+        FriendRequest.status == FriendRequestStatus.pending
+    ).first()
+
+    if not request:
+        raise HTTPException(status_code=404, detail="요청을 찾을 수 없습니다.")
+
+    request.status = FriendRequestStatus.accepted if accept else FriendRequestStatus.rejected
+    request.updated_at = datetime.utcnow()
+
+    # 친구 수락 시 friends 테이블에도 저장
+    if accept:
+        user_ids = sorted([request.from_user_id, request.to_user_id])
+        friend = Friend(
+            user_id_1=user_ids[0],
+            user_id_2=user_ids[1]
+        )
+        db.add(friend)
+
+    db.commit()
+
+
+def get_friend_list(db: Session, user_id: int):
+    friends = db.query(Friend).filter(
+        (Friend.user_id_1 == user_id) | (Friend.user_id_2 == user_id)
+    ).all()
+
+    result = []
+    for f in friends:
+        friend_id = f.user_id_2 if f.user_id_1 == user_id else f.user_id_1
+        result.append(friend_id)
+
+    return result
+
+def get_public_characters_of_friend(db: Session, current_user_id: int, friend_id: int):
+    # 친구 관계 확인
+    user_ids = sorted([current_user_id, friend_id])
+    is_friend = db.query(Friend).filter(
+        Friend.user_id_1 == user_ids[0],
+        Friend.user_id_2 == user_ids[1]
+    ).first()
+
+    if not is_friend:
+        raise HTTPException(status_code=403, detail="친구가 아닙니다.")
+
+    # 공개된 캐릭터 목록
+    characters = db.query(Character).filter(
+        Character.user_id == friend_id,
+        Character.is_public == True
+    ).all()
+
+    return characters
+
+def get_public_homeworks_of_friend_character(
+    db: Session,
+    current_user_id: int,
+    friend_id: int,
+    character_id: int
+):
+    # 1. 친구인지 확인
+    user_ids = sorted([current_user_id, friend_id])
+    is_friend = db.query(Friend).filter(
+        Friend.user_id_1 == user_ids[0],
+        Friend.user_id_2 == user_ids[1]
+    ).first()
+    if not is_friend:
+        raise HTTPException(status_code=403, detail="친구가 아닙니다.")
+
+    # 2. 해당 캐릭터가 공개인지 확인
+    character = db.query(Character).filter(
+        Character.id == character_id,
+        Character.user_id == friend_id,
+        Character.is_public == True
+    ).first()
+    if not character:
+        raise HTTPException(status_code=404, detail="공개된 캐릭터를 찾을 수 없습니다.")
+
+    # 3. 공개된 숙제만 조회
+    results = db.query(HomeworkType).join(CharacterHomework).filter(
+        CharacterHomework.character_id == character_id,
+        HomeworkType.is_public == True
+    ).all()
+
+    return results
+
+def delete_friend(db: Session, user_id: int, friend_id: int):
+    user_ids = sorted([user_id, friend_id])
+
+    friend = db.query(Friend).filter(
+        Friend.user_id_1 == user_ids[0],
+        Friend.user_id_2 == user_ids[1]
+    ).first()
+
+    if not friend:
+        raise HTTPException(status_code=404, detail="친구 관계가 존재하지 않습니다.")
+
+    db.delete(friend)
+    db.commit()
diff --git a/app/services/user_service.py b/app/services/user_service.py
new file mode 100644
index 0000000..f989084
--- /dev/null
+++ b/app/services/user_service.py
@@ -0,0 +1,68 @@
+from fastapi import HTTPException
+from sqlalchemy.orm import Session
+
+from app.models.user import User
+from app.models.friend import Friend, FriendRequest, FriendRequestStatus
+from app.models.character import Character
+
+def get_user_public_info(
+    db: Session,
+    current_user_id: int,
+    target_email: str
+):
+    target_user = db.query(User).filter(User.email == target_email).first()
+    if not target_user:
+        raise HTTPException(status_code=404, detail="해당 유저를 찾을 수 없습니다.")
+
+    if target_user.id == current_user_id:
+        raise HTTPException(status_code=400, detail="자기 자신은 검색할 수 없습니다.")
+
+    user_ids = sorted([current_user_id, target_user.id])
+    is_friend = db.query(Friend).filter(
+        Friend.user_id_1 == user_ids[0],
+        Friend.user_id_2 == user_ids[1]
+    ).first() is not None
+
+    request_sent = db.query(FriendRequest).filter(
+        FriendRequest.from_user_id == current_user_id,
+        FriendRequest.to_user_id == target_user.id,
+        FriendRequest.status == FriendRequestStatus.pending
+    ).first() is not None
+
+    request_received = db.query(FriendRequest).filter(
+        FriendRequest.from_user_id == target_user.id,
+        FriendRequest.to_user_id == current_user_id,
+        FriendRequest.status == FriendRequestStatus.pending
+    ).first() is not None
+
+    return {
+        "id": target_user.id,
+        "email": target_user.email,
+        "is_friend": is_friend,
+        "request_sent": request_sent,
+        "request_received": request_received,
+    }
+
+def get_user_by_character(
+    db: Session,
+    server: str,
+    name: str
+):
+    character = db.query(Character).filter(
+        Character.server == server,
+        Character.name == name
+    ).first()
+
+    if not character:
+        raise HTTPException(status_code=404, detail="캐릭터를 찾을 수 없습니다.")
+
+    user = db.query(User).filter(User.id == character.user_id).first()
+
+    return {
+        "user_id": user.id,
+        "email": user.email,
+        "character_id": character.id,
+        "character_name": character.name,
+        "server": character.server,
+        "is_public": character.is_public
+    }
\ No newline at end of file