diff --git a/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc.py b/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc.py
index ada385f0abd4..fbae8f1ebdba 100644
--- a/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc.py
+++ b/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc.py
@@ -179,8 +179,11 @@ def __init__(
         if not self._grpc_channel:
             self._grpc_channel = type(self).create_channel(
                 self._host,
+                # use the credentials which are saved
                 credentials=self._credentials,
-                credentials_file=credentials_file,
+                # Set ``credentials_file`` to ``None`` here as
+                # the credentials that we saved earlier should be used.
+                credentials_file=None,
                 scopes=self._scopes,
                 ssl_credentials=self._ssl_channel_credentials,
                 quota_project_id=quota_project_id,
diff --git a/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc_asyncio.py b/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc_asyncio.py
index 416ec7b9ca06..913bf9552a04 100644
--- a/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc_asyncio.py
+++ b/packages/google-cloud-private-catalog/google/cloud/privatecatalog_v1beta1/services/private_catalog/transports/grpc_asyncio.py
@@ -224,8 +224,11 @@ def __init__(
         if not self._grpc_channel:
             self._grpc_channel = type(self).create_channel(
                 self._host,
+                # use the credentials which are saved
                 credentials=self._credentials,
-                credentials_file=credentials_file,
+                # Set ``credentials_file`` to ``None`` here as
+                # the credentials that we saved earlier should be used.
+                credentials_file=None,
                 scopes=self._scopes,
                 ssl_credentials=self._ssl_channel_credentials,
                 quota_project_id=quota_project_id,
diff --git a/packages/google-cloud-private-catalog/tests/unit/gapic/privatecatalog_v1beta1/test_private_catalog.py b/packages/google-cloud-private-catalog/tests/unit/gapic/privatecatalog_v1beta1/test_private_catalog.py
index e4006382ce80..05c4ad227f11 100644
--- a/packages/google-cloud-private-catalog/tests/unit/gapic/privatecatalog_v1beta1/test_private_catalog.py
+++ b/packages/google-cloud-private-catalog/tests/unit/gapic/privatecatalog_v1beta1/test_private_catalog.py
@@ -512,21 +512,28 @@ def test_private_catalog_client_client_options_scopes(
 
 
 @pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
+    "client_class,transport_class,transport_name,grpc_helpers",
     [
-        (PrivateCatalogClient, transports.PrivateCatalogGrpcTransport, "grpc"),
+        (
+            PrivateCatalogClient,
+            transports.PrivateCatalogGrpcTransport,
+            "grpc",
+            grpc_helpers,
+        ),
         (
             PrivateCatalogAsyncClient,
             transports.PrivateCatalogGrpcAsyncIOTransport,
             "grpc_asyncio",
+            grpc_helpers_async,
         ),
     ],
 )
 def test_private_catalog_client_client_options_credentials_file(
-    client_class, transport_class, transport_name
+    client_class, transport_class, transport_name, grpc_helpers
 ):
     # Check the case credentials file is provided.
     options = client_options.ClientOptions(credentials_file="credentials.json")
+
     with mock.patch.object(transport_class, "__init__") as patched:
         patched.return_value = None
         client = client_class(client_options=options, transport=transport_name)
@@ -562,6 +569,72 @@ def test_private_catalog_client_client_options_from_dict():
         )
 
 
+@pytest.mark.parametrize(
+    "client_class,transport_class,transport_name,grpc_helpers",
+    [
+        (
+            PrivateCatalogClient,
+            transports.PrivateCatalogGrpcTransport,
+            "grpc",
+            grpc_helpers,
+        ),
+        (
+            PrivateCatalogAsyncClient,
+            transports.PrivateCatalogGrpcAsyncIOTransport,
+            "grpc_asyncio",
+            grpc_helpers_async,
+        ),
+    ],
+)
+def test_private_catalog_client_create_channel_credentials_file(
+    client_class, transport_class, transport_name, grpc_helpers
+):
+    # Check the case credentials file is provided.
+    options = client_options.ClientOptions(credentials_file="credentials.json")
+
+    with mock.patch.object(transport_class, "__init__") as patched:
+        patched.return_value = None
+        client = client_class(client_options=options, transport=transport_name)
+        patched.assert_called_once_with(
+            credentials=None,
+            credentials_file="credentials.json",
+            host=client.DEFAULT_ENDPOINT,
+            scopes=None,
+            client_cert_source_for_mtls=None,
+            quota_project_id=None,
+            client_info=transports.base.DEFAULT_CLIENT_INFO,
+            always_use_jwt_access=True,
+        )
+
+    # test that the credentials from file are saved and used as the credentials.
+    with mock.patch.object(
+        google.auth, "load_credentials_from_file", autospec=True
+    ) as load_creds, mock.patch.object(
+        google.auth, "default", autospec=True
+    ) as adc, mock.patch.object(
+        grpc_helpers, "create_channel"
+    ) as create_channel:
+        creds = ga_credentials.AnonymousCredentials()
+        file_creds = ga_credentials.AnonymousCredentials()
+        load_creds.return_value = (file_creds, None)
+        adc.return_value = (creds, None)
+        client = client_class(client_options=options, transport=transport_name)
+        create_channel.assert_called_with(
+            "cloudprivatecatalog.googleapis.com:443",
+            credentials=file_creds,
+            credentials_file=None,
+            quota_project_id=None,
+            default_scopes=("https://www.googleapis.com/auth/cloud-platform",),
+            scopes=None,
+            default_host="cloudprivatecatalog.googleapis.com",
+            ssl_credentials=None,
+            options=[
+                ("grpc.max_send_message_length", -1),
+                ("grpc.max_receive_message_length", -1),
+            ],
+        )
+
+
 @pytest.mark.parametrize("request_type", [private_catalog.SearchCatalogsRequest, dict,])
 def test_search_catalogs(request_type, transport: str = "grpc"):
     client = PrivateCatalogClient(