diff --git a/fastapi_users/authentication/__init__.py b/fastapi_users/authentication/__init__.py
index bed698e0..5c326f27 100644
--- a/fastapi_users/authentication/__init__.py
+++ b/fastapi_users/authentication/__init__.py
@@ -8,10 +8,10 @@ from fastapi_users.models import UserDB
 
 class BaseAuthentication:
 
-    userDB: BaseUserDatabase
+    user_db: BaseUserDatabase
 
-    def __init__(self, userDB: BaseUserDatabase):
-        self.userDB = userDB
+    def __init__(self, user_db: BaseUserDatabase):
+        self.user_db = user_db
 
     async def get_login_response(self, user: UserDB, response: Response):
         raise NotImplementedError()
diff --git a/fastapi_users/authentication/jwt.py b/fastapi_users/authentication/jwt.py
index cb3e0f89..deb6af8c 100644
--- a/fastapi_users/authentication/jwt.py
+++ b/fastapi_users/authentication/jwt.py
@@ -50,7 +50,7 @@ class JWTAuthentication(BaseAuthentication):
             except jwt.PyJWTError:
                 raise credentials_exception
 
-            user = await self.userDB.get(user_id)
+            user = await self.user_db.get(user_id)
             if user is None or not user.is_active:
                 raise credentials_exception
 
diff --git a/fastapi_users/router.py b/fastapi_users/router.py
index 068e2967..4d93e582 100644
--- a/fastapi_users/router.py
+++ b/fastapi_users/router.py
@@ -10,21 +10,21 @@ from fastapi_users.password import get_password_hash
 
 
 class UserRouter:
-    def __new__(cls, userDB: BaseUserDatabase, auth: BaseAuthentication) -> APIRouter:
+    def __new__(cls, user_db: BaseUserDatabase, auth: BaseAuthentication) -> APIRouter:
         router = APIRouter()
 
         @router.post("/register", response_model=User)
         async def register(user: UserCreate):
             hashed_password = get_password_hash(user.password)
             db_user = UserDB(**user.dict(), hashed_password=hashed_password)
-            created_user = await userDB.create(db_user)
+            created_user = await user_db.create(db_user)
             return created_user
 
         @router.post("/login")
         async def login(
             response: Response, credentials: OAuth2PasswordRequestForm = Depends()
         ):
-            user = await userDB.authenticate(credentials)
+            user = await user_db.authenticate(credentials)
 
             if user is None:
                 raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST)
diff --git a/tests/conftest.py b/tests/conftest.py
index 4eec8f0a..42025ff5 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -61,7 +61,7 @@ class MockAuthentication(BaseAuthentication):
         return {"token": user.id}
 
     async def authenticate(self, token: str) -> UserDB:
-        user = await self.userDB.get(token)
+        user = await self.user_db.get(token)
         if user is None or not user.is_active:
             raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED)
         return user