diff --git a/airflow-core/src/airflow/api_fastapi/core_api/app.py b/airflow-core/src/airflow/api_fastapi/core_api/app.py
index 253ef206e13a9..ad8938de994b6 100644
--- a/airflow-core/src/airflow/api_fastapi/core_api/app.py
+++ b/airflow-core/src/airflow/api_fastapi/core_api/app.py
@@ -30,7 +30,6 @@
 from starlette.templating import Jinja2Templates
 
 from airflow.api_fastapi.auth.tokens import get_signing_key
-from airflow.api_fastapi.core_api.middleware import FlaskExceptionsMiddleware
 from airflow.exceptions import AirflowException
 from airflow.settings import AIRFLOW_PATH
 
@@ -176,8 +175,9 @@ def init_error_handlers(app: FastAPI) -> None:
 def init_middlewares(app: FastAPI) -> None:
     from airflow.configuration import conf
 
-    app.add_middleware(FlaskExceptionsMiddleware)
-    if conf.getboolean("core", "simple_auth_manager_all_admins"):
+    if "SimpleAuthManager" in conf.get("core", "auth_manager") and conf.getboolean(
+        "core", "simple_auth_manager_all_admins"
+    ):
         from airflow.api_fastapi.auth.managers.simple.middleware import SimpleAllAdminMiddleware
 
         app.add_middleware(SimpleAllAdminMiddleware)
diff --git a/airflow-core/src/airflow/api_fastapi/core_api/middleware.py b/airflow-core/src/airflow/api_fastapi/core_api/middleware.py
deleted file mode 100644
index e88c9acc5438a..0000000000000
--- a/airflow-core/src/airflow/api_fastapi/core_api/middleware.py
+++ /dev/null
@@ -1,39 +0,0 @@
-# Licensed to the Apache Software Foundation (ASF) under one
-# or more contributor license agreements.  See the NOTICE file
-# distributed with this work for additional information
-# regarding copyright ownership.  The ASF licenses this file
-# to you under the Apache License, Version 2.0 (the
-# "License"); you may not use this file except in compliance
-# with the License.  You may obtain a copy of the License at
-#
-#   http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing,
-# software distributed under the License is distributed on an
-# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-# KIND, either express or implied.  See the License for the
-# specific language governing permissions and limitations
-# under the License.
-from __future__ import annotations
-
-from fastapi import HTTPException, Request
-from starlette.middleware.base import BaseHTTPMiddleware
-
-
-# Custom Middleware Class
-class FlaskExceptionsMiddleware(BaseHTTPMiddleware):
-    """Middleware that converts exceptions thrown in the Flask application to Fastapi exceptions."""
-
-    async def dispatch(self, request: Request, call_next):
-        response = await call_next(request)
-
-        # Check if the WSGI response contains an error
-        if response.status_code >= 400 and response.media_type == "application/json":
-            body = await response.json()
-            if "error" in body:
-                # Transform the WSGI app's exception into a FastAPI HTTPException
-                raise HTTPException(
-                    status_code=response.status_code,
-                    detail=body["error"],
-                )
-        return response