diff --git a/src/baby_monitor/models/__init__.py b/src/baby_monitor/models/__init__.py
new file mode 100644
index 0000000..33ff22f
--- /dev/null
+++ b/src/baby_monitor/models/__init__.py
@@ -0,0 +1,3 @@
+from .auth import LoginRequest, LoginResponse
+
+__all__ = ["LoginRequest", "LoginResponse"]
diff --git a/src/baby_monitor/models/auth.py b/src/baby_monitor/models/auth.py
new file mode 100644
index 0000000..62a6a20
--- /dev/null
+++ b/src/baby_monitor/models/auth.py
@@ -0,0 +1,19 @@
+"""Authentication models for request and response validation."""
+
+from pydantic import BaseModel
+
+
+class LoginRequest(BaseModel):
+    """Request model for user login."""
+
+    username: str
+    password: str
+
+
+class LoginResponse(BaseModel):
+    """Response model for successful login."""
+
+    message: str
+    username: str
+    access_token: str
+    token_type: str = "bearer"
diff --git a/src/baby_monitor/models/db/__init__.py b/src/baby_monitor/models/db/__init__.py
new file mode 100644
index 0000000..7469036
--- /dev/null
+++ b/src/baby_monitor/models/db/__init__.py
@@ -0,0 +1,5 @@
+"""Database models package."""
+
+from baby_monitor.models.db.user import User
+
+__all__ = ["User"]
diff --git a/src/baby_monitor/models/db/user.py b/src/baby_monitor/models/db/user.py
new file mode 100644
index 0000000..31f3bdc
--- /dev/null
+++ b/src/baby_monitor/models/db/user.py
@@ -0,0 +1,20 @@
+"""Database models."""
+
+from sqlalchemy import Column, Integer, String, DateTime
+from datetime import datetime
+
+from baby_monitor.repositories.dependencies.get_database import Base
+
+
+class User(Base):
+    """User database model."""
+
+    __tablename__ = "users"
+
+    id = Column(Integer, primary_key=True, index=True)
+    username = Column(String, unique=True, index=True, nullable=False)
+    hashed_password = Column(String, nullable=False)
+    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
+
+    def __repr__(self) -> str:
+        return f"<User(id={self.id}, username='{self.username}')>"