diff --git a/addons/calendar/models/calendar_event.py b/addons/calendar/models/calendar_event.py
index 1192cc0bdbf..f01f03fb1d0 100644
--- a/addons/calendar/models/calendar_event.py
+++ b/addons/calendar/models/calendar_event.py
@@ -106,9 +106,14 @@ class Meeting(models.Model):
     def _get_time_fields(self):
         return {'start', 'stop', 'start_date', 'stop_date'}
 
+    @api.model
+    def _get_custom_fields(self):
+        all_fields = self.fields_get(attributes=['manual'])
+        return {fname for fname in all_fields if all_fields[fname]['manual']}
+
     @api.model
     def _get_public_fields(self):
-        return self._get_recurrent_fields() | self._get_time_fields() | {
+        return self._get_recurrent_fields() | self._get_time_fields() | self._get_custom_fields() | {
             'id', 'active', 'allday',
             'duration', 'user_id', 'interval',
             'count', 'rrule', 'recurrence_id', 'show_as'}