diff --git a/faassupervisor/storage/config.py b/faassupervisor/storage/config.py
index c83c610..64ffe42 100644
--- a/faassupervisor/storage/config.py
+++ b/faassupervisor/storage/config.py
@@ -234,7 +234,7 @@ def upload_output(self, output_dir_path):
             provider_type = StrUtils.get_storage_type(output['storage_provider'])
             provider_id = StrUtils.get_storage_id(output['storage_provider'])
             for file_path in output_files:
-                file_name = file_path.replace(f'{output_dir_path}/', '').strip()
+                file_name = file_path.replace(f'{output_dir_path}/', '').strip().lstrip('/')
                 prefix_ok = False
                 suffix_ok = False
                 # Check prefixes
diff --git a/test/unit/faassupervisor/storage.py b/test/unit/faassupervisor/storage.py
index 7d42832..9b7228d 100644
--- a/test/unit/faassupervisor/storage.py
+++ b/test/unit/faassupervisor/storage.py
@@ -260,7 +260,7 @@ def test_upload_output(self, mock_minio, mock_s3, mock_get_files):
                 '/tmp/test/result-file.out',
                 '/tmp/test/file2.txt',
                 '/tmp/test/file2.out',
-                '/tmp/test/\nfile3.out'
+                '/tmp/test/\n/file3.out'
             ]
             mock_get_files.return_value = files
             StorageConfig().upload_output('/tmp/test')
@@ -274,7 +274,7 @@ def test_upload_output(self, mock_minio, mock_s3, mock_get_files):
                 self.assertEqual(mock_s3.call_args_list[i],
                                  call(f, f.split('/')[3], 'bucket/folder'))
             self.assertEqual(mock_s3.call_args_list[6],
-                             call('/tmp/test/\nfile3.out', 'file3.out', 'bucket/folder'))
+                             call('/tmp/test/\n/file3.out', 'file3.out', 'bucket/folder'))
 
 #    def test_upload_real_output(self):
 #        with mock.patch.dict('os.environ',