diff --git a/addons/google_calendar/models/calendar.py b/addons/google_calendar/models/calendar.py
index 11364eee474..17ebd7dd838 100644
--- a/addons/google_calendar/models/calendar.py
+++ b/addons/google_calendar/models/calendar.py
@@ -202,7 +202,7 @@ class Meeting(models.Model):
         }
         if self.privacy:
             values['visibility'] = self.privacy
-        if self.user_id != self.env.user:
+        if self.user_id and self.user_id != self.env.user:
             values['extendedProperties']['shared']['%s_owner_id' % self.env.cr.dbname] = self.user_id.id
 
         if not self.active:
diff --git a/addons/google_calendar/tests/test_sync_google2odoo.py b/addons/google_calendar/tests/test_sync_google2odoo.py
index 4e2d1a7d809..01e53a625fd 100644
--- a/addons/google_calendar/tests/test_sync_google2odoo.py
+++ b/addons/google_calendar/tests/test_sync_google2odoo.py
@@ -54,6 +54,57 @@ class TestSyncGoogle2Odoo(TransactionCase):
         self.assertEqual(event.partner_ids, event.attendee_ids.partner_id)
         self.assertEqual('needsAction', admin_attendee.state)
 
+    def test_invalid_owner_property(self):
+        values = {
+            'id': 'oj44nep1ldf8a3ll02uip0c9aa',
+            'description': 'Small mini desc',
+            'organizer': {'email': 'odoocalendarref@gmail.com', 'self': True},
+            'summary': 'Pricing new update',
+            'visibility': 'public',
+            'attendees': [],
+            'reminders': {'useDefault': True},
+            'start': {
+                'dateTime': '2020-01-13T16:55:00+01:00',
+                'timeZone': 'Europe/Brussels'
+            },
+            'extendedProperties': {
+                'shared':  {'%s_owner_id' % self.env.cr.dbname: "invalid owner id"}
+            },
+            'end': {
+                'dateTime': '2020-01-13T19:55:00+01:00',
+                'timeZone': 'Europe/Brussels'
+            },
+        }
+        self.env['calendar.event']._sync_google2odoo(GoogleEvent([values]))
+        event = self.env['calendar.event'].search([('google_id', '=', values.get('id'))])
+        self.assertEqual(event.user_id, self.env.user)
+
+    def test_valid_owner_property(self):
+        user = new_test_user(self.env, login='calendar-user')
+        values = {
+            'id': 'oj44nep1ldf8a3ll02uip0c9aa',
+            'description': 'Small mini desc',
+            'organizer': {'email': 'odoocalendarref@gmail.com', 'self': True},
+            'summary': 'Pricing new update',
+            'visibility': 'public',
+            'attendees': [],
+            'reminders': {'useDefault': True},
+            'start': {
+                'dateTime': '2020-01-13T16:55:00+01:00',
+                'timeZone': 'Europe/Brussels'
+            },
+            'extendedProperties': {
+                'shared':  {'%s_owner_id' % self.env.cr.dbname: str(user.id)}
+            },
+            'end': {
+                'dateTime': '2020-01-13T19:55:00+01:00',
+                'timeZone': 'Europe/Brussels'
+            },
+        }
+        self.env['calendar.event']._sync_google2odoo(GoogleEvent([values]))
+        event = self.env['calendar.event'].search([('google_id', '=', values.get('id'))])
+        self.assertEqual(event.user_id, user)
+
     def test_cancelled(self):
         google_id = 'oj44nep1ldf8a3ll02uip0c9aa'
         event = self.env['calendar.event'].create({
diff --git a/addons/google_calendar/tests/test_sync_odoo2google.py b/addons/google_calendar/tests/test_sync_odoo2google.py
index 7028d797470..b6a42fd14c2 100644
--- a/addons/google_calendar/tests/test_sync_odoo2google.py
+++ b/addons/google_calendar/tests/test_sync_odoo2google.py
@@ -84,6 +84,18 @@ class TestSyncOdoo2Google(TransactionCase):
             'extendedProperties': {'shared': {'%s_odoo_id' % self.env.cr.dbname: event.id}}
         })
 
+    def test_event_without_user(self):
+        event = self.env['calendar.event'].create({
+            'name': "Event",
+            'start': datetime(2020, 1, 15, 8, 0),
+            'stop': datetime(2020, 1, 15, 18, 0),
+            'user_id': False,
+            'privacy': 'private',
+            'need_sync': False,
+        })
+        values = event._google_values()
+        self.assertFalse('%s_owner_id' % self.env.cr.dbname in values.get('extendedProperties', {}).get('shared', {}))
+
     @patch_api
     def test_event_allday_creation(self):
         event = self.env['calendar.event'].create({
diff --git a/addons/google_calendar/utils/google_event.py b/addons/google_calendar/utils/google_event.py
index 9ebbd5ed7b2..8c11af3ce41 100644
--- a/addons/google_calendar/utils/google_event.py
+++ b/addons/google_calendar/utils/google_event.py
@@ -125,11 +125,17 @@ class GoogleEvent(abc.Set):
         # UserA creates an event in Odoo (he is the owner) but userB syncs first.
         # There is no way to insert the event into userA's calendar since we don't have
         # any authentication access. The event is therefore inserted into userB's calendar
-        # (he is the orginizer in Google). The "real" owner (in Odoo) is stored as an
+        # (he is the organizer in Google). The "real" owner (in Odoo) is stored as an
         # extended property. There is currently no support to "transfert" ownership when
         # userA syncs his calendar the first time.
         real_owner_id = self.extendedProperties and self.extendedProperties.get('shared', {}).get('%s_owner_id' % env.cr.dbname)
-        real_owner = real_owner_id and env['res.users'].browse(int(real_owner_id))
+        try:
+            # If we create an event without user_id, the event properties will be 'false'
+            # and python will interpret this a a NoneType, that's why we have the 'except TypeError'
+            real_owner_id = int(real_owner_id)
+        except (ValueError, TypeError):
+            real_owner_id = False
+        real_owner = real_owner_id and env['res.users'].browse(real_owner_id) or env['res.users']
         if real_owner_id and real_owner.exists():
             return real_owner
         elif self.organizer and self.organizer.get('self'):