diff --git a/addons/google_calendar/controllers/main.py b/addons/google_calendar/controllers/main.py
index 40c8b736ab9..adc6bb90e64 100644
--- a/addons/google_calendar/controllers/main.py
+++ b/addons/google_calendar/controllers/main.py
@@ -18,7 +18,8 @@ class GoogleCalendarController(http.Controller):
             this URL for authorization for example
         """
         if model == 'calendar.event':
-            GoogleCal = GoogleCalendarService(request.env['google.service'])
+            base_url = request.httprequest.url_root.strip('/')
+            GoogleCal = GoogleCalendarService(request.env['google.service'].with_context(base_url=base_url))
 
             # Checking that admin have already configured Google API for google synchronization !
             client_id = request.env['google.service']._get_client_id('calendar')
diff --git a/addons/google_calendar/utils/google_calendar.py b/addons/google_calendar/utils/google_calendar.py
index 3da73fc1b9a..a2bf89bd32d 100644
--- a/addons/google_calendar/utils/google_calendar.py
+++ b/addons/google_calendar/utils/google_calendar.py
@@ -112,10 +112,11 @@ class GoogleCalendarService():
             's': 'calendar',
             'f': from_url
         }
+        base_url = self.google_service._context.get('base_url') or self.google_service.get_base_url()
         return self.google_service._get_authorize_uri(
             'calendar',
             self._get_calendar_scope(),
-            self.google_service.get_base_url() + '/google_account/authentication',
+            base_url + '/google_account/authentication',
             state=json.dumps(state),
             approval_prompt='force',
             access_type='offline'