diff --git a/src/promptflow/promptflow/_sdk/_service/entry.py b/src/promptflow/promptflow/_sdk/_service/entry.py
index d2596218296f..719f7f43fb15 100644
--- a/src/promptflow/promptflow/_sdk/_service/entry.py
+++ b/src/promptflow/promptflow/_sdk/_service/entry.py
@@ -28,11 +28,11 @@
 app = None
 
 
-def get_app(environ, start_response):
+def get_app():
     global app
     if app is None:
         app, _ = create_app()
-    return app.wsgi_app(environ, start_response)
+    return app
 
 
 def add_start_service_action(subparsers):
@@ -70,7 +70,7 @@ def start_service(args):
     # User Agent will be set based on header in request, so not set globally here.
     os.environ[PF_NO_INTERACTIVE_LOGIN] = "true"
     port = args.port
-    app, _ = create_app()
+    get_app()
 
     def validate_port(port, force_start):
         if is_port_in_use(port):
@@ -88,15 +88,30 @@ def validate_port(port, force_start):
         port = get_port_from_config(create_if_not_exists=True)
         validate_port(port, args.force)
     # Set host to localhost, only allow request from localhost.
-    cmd = ["waitress-serve", f"--listen=127.0.0.1:{port}", "promptflow._sdk._service.entry:get_app"]
+    cmd = [
+        "-m",
+        "waitress",
+        "--host",
+        "127.0.0.1",
+        f"--port={port}",
+        "--call",
+        "promptflow._sdk._service.entry:get_app",
+    ]
+    if sys.executable.endswith("pfcli.exe"):
+        cmd = ["python"] + cmd
+    else:
+        cmd = [sys.executable] + cmd
     if args.synchronous:
         subprocess.call(cmd)
     else:
         # Start a pfs process using detach mode
         if platform.system() == "Windows":
-            subprocess.Popen(cmd, creationflags=subprocess.CREATE_NEW_PROCESS_GROUP)
+            if sys.executable.endswith("pfcli.exe"):
+                os.spawnv(os.P_DETACH, "python", cmd)
+            else:
+                os.spawnv(os.P_DETACH, sys.executable, cmd)
         else:
-            subprocess.Popen(cmd, start_new_session=True)
+            os.system(" ".join(["nohup"] + cmd + ["&"]))
     is_healthy = check_pfs_service_status(port)
     if is_healthy:
         app.logger.info(