diff --git a/README.rst b/README.rst
index 1912a17..637b8f8 100644
--- a/README.rst
+++ b/README.rst
@@ -128,6 +128,9 @@ httpserver mode
 This mode is faster than ``cmd`` and a bit slower than ``tcpserver``, but you can use official MJML API https://mjml.io/api
 or run your own HTTP-server (for example https://github.com/danihodovic/mjml-server) to render templates.
 
+You can use any Authentication backend supported by requests (or provide your own). 
+See https://requests.readthedocs.io/en/latest/user/authentication/ for details.
+
 Configure your Django::
 
   MJML_BACKEND_MODE = 'httpserver'
diff --git a/mjml/settings.py b/mjml/settings.py
index 714d92a..b3e1fa8 100644
--- a/mjml/settings.py
+++ b/mjml/settings.py
@@ -1,4 +1,8 @@
 from django.conf import settings
+try:
+    from requests.auth import AuthBase
+except ImportError:
+    AuthBase = None
 
 MJML_BACKEND_MODE = getattr(settings, 'MJML_BACKEND_MODE', 'cmd')
 assert MJML_BACKEND_MODE in {'cmd', 'tcpserver', 'httpserver'}
@@ -24,6 +28,10 @@
     assert 'URL' in t and isinstance(t['URL'], str)
     if 'HTTP_AUTH' in t:
         http_auth = t['HTTP_AUTH']
-        assert isinstance(http_auth, (type(None), list, tuple))
-        if http_auth is not None:
+        if AuthBase:
+            assert isinstance(http_auth, (type(None), list, tuple, AuthBase))
+        else:  
+            assert isinstance(http_auth, (type(None), list, tuple))
+
+        if isinstance(http_auth, (list, tuple)):
             assert len(http_auth) == 2 and isinstance(http_auth[0], str) and isinstance(http_auth[1], str)
diff --git a/mjml/tools.py b/mjml/tools.py
index c064fdd..1faabc7 100644
--- a/mjml/tools.py
+++ b/mjml/tools.py
@@ -109,7 +109,12 @@ def _mjml_render_by_httpserver(mjml_code: str) -> str:
     timeouts = 0
     for server_conf in servers:
         http_auth = server_conf.get('HTTP_AUTH')
-        auth = requests.auth.HTTPBasicAuth(*http_auth) if http_auth else None
+
+        auth = (
+            http_auth
+            if isinstance(http_auth, (type(None), requests.auth.AuthBase))
+            else requests.auth.HTTPBasicAuth(*http_auth)
+        )
 
         try:
             response = requests.post(
diff --git a/testprj/tests_httpserver.py b/testprj/tests_httpserver.py
index 2016295..6cb5dd2 100644
--- a/testprj/tests_httpserver.py
+++ b/testprj/tests_httpserver.py
@@ -67,7 +67,7 @@ def test_http_server_error(self) -> None:
         self.assertIn(' Tag: mj-button Message: mj-button ', str(cm.exception))
 
     @mock.patch('requests.post')
-    def test_http_auth(self, post_mock) -> None:
+    def test_http_basic_auth(self, post_mock) -> None:
         with safe_change_mjml_settings():
             for server_conf in mjml_settings.MJML_HTTPSERVERS:
                 server_conf['HTTP_AUTH'] = ('testuser', 'testpassword')
@@ -93,6 +93,33 @@ def test_http_auth(self, post_mock) -> None:
             self.assertEqual(post_mock.call_args[1]['auth'].username, 'testuser')
             self.assertEqual(post_mock.call_args[1]['auth'].password, 'testpassword')
 
+    @mock.patch('requests.post')
+    def test_http_auth(self, post_mock) -> None:
+        with safe_change_mjml_settings():
+            for server_conf in mjml_settings.MJML_HTTPSERVERS:
+                server_conf['HTTP_AUTH'] = requests.auth.HTTPBasicAuth('testuser', 'testpassword')
+
+            response = requests.Response()
+            response.status_code = 200
+            response._content = force_bytes(json.dumps({
+                'errors': [],
+                'html': 'html_string',
+                'mjml': 'mjml_string',
+                'mjml_version': '4.5.1',
+            }))
+            response.encoding = 'utf-8'
+            response.headers['Content-Type'] = 'text/html; charset=utf-8'
+            response.headers['Content-Length'] = len(response._content)
+            post_mock.return_value = response
+
+            render_tpl(self.TPLS['simple'])
+
+            self.assertTrue(post_mock.called)
+            self.assertIn('auth', post_mock.call_args[1])
+            self.assertIsInstance(post_mock.call_args[1]['auth'], requests.auth.HTTPBasicAuth)
+            self.assertEqual(post_mock.call_args[1]['auth'].username, 'testuser')
+            self.assertEqual(post_mock.call_args[1]['auth'].password, 'testpassword')
+
     @unittest.skip('to run locally')
     def test_public_api(self) -> None:
         with safe_change_mjml_settings():