diff --git a/addons/crm/models/crm_lead_scoring_frequency.py b/addons/crm/models/crm_lead_scoring_frequency.py
index fc6d0bdbbbe..85b5c77b0f2 100644
--- a/addons/crm/models/crm_lead_scoring_frequency.py
+++ b/addons/crm/models/crm_lead_scoring_frequency.py
@@ -18,4 +18,7 @@ class FrequencyField(models.Model):
     _description = 'Fields that can be used for predictive lead scoring computation'
 
     name = fields.Char(related="field_id.field_description")
-    field_id = fields.Many2one('ir.model.fields', domain=[('model_id.model', '=', 'crm.lead')], required=True)
+    field_id = fields.Many2one(
+        'ir.model.fields', domain=[('model_id.model', '=', 'crm.lead')], required=True,
+        ondelete='cascade',
+    )
diff --git a/addons/google_drive/models/google_drive.py b/addons/google_drive/models/google_drive.py
index 26246870da5..14573d42a82 100644
--- a/addons/google_drive/models/google_drive.py
+++ b/addons/google_drive/models/google_drive.py
@@ -175,7 +175,7 @@ class GoogleDrive(models.Model):
         return config_values
 
     name = fields.Char('Template Name', required=True)
-    model_id = fields.Many2one('ir.model', 'Model', required=True)
+    model_id = fields.Many2one('ir.model', 'Model', required=True, ondelete='cascade')
     model = fields.Char('Related Model', related='model_id.model', readonly=True)
     filter_id = fields.Many2one('ir.filters', 'Filter', domain="[('model_id', '=', model)]")
     google_drive_template_url = fields.Char('Template URL', required=True)
diff --git a/addons/sms/models/sms_template.py b/addons/sms/models/sms_template.py
index e1ba74d3bb1..cf2120c8a5e 100644
--- a/addons/sms/models/sms_template.py
+++ b/addons/sms/models/sms_template.py
@@ -20,7 +20,7 @@ class SMSTemplate(models.Model):
     model_id = fields.Many2one(
         'ir.model', string='Applies to', required=True,
         domain=['&', ('is_mail_thread_sms', '=', True), ('transient', '=', False)],
-        help="The type of document this template can be used with")
+        help="The type of document this template can be used with", ondelete='cascade')
     model = fields.Char('Related Document Model', related='model_id.model', index=True, store=True, readonly=True)
     body = fields.Char('Body', translate=True, required=True)
     lang = fields.Char('Language', help="Use this field to either force a specific language (ISO code) or dynamically "
diff --git a/odoo/addons/base/models/ir_actions.py b/odoo/addons/base/models/ir_actions.py
index 5680c1f88e3..8c135d751af 100644
--- a/odoo/addons/base/models/ir_actions.py
+++ b/odoo/addons/base/models/ir_actions.py
@@ -576,7 +576,7 @@ class IrServerObjectLines(models.Model):
     _sequence = 'ir_actions_id_seq'
 
     server_id = fields.Many2one('ir.actions.server', string='Related Server Action', ondelete='cascade')
-    col1 = fields.Many2one('ir.model.fields', string='Field', required=True)
+    col1 = fields.Many2one('ir.model.fields', string='Field', required=True, ondelete='cascade')
     value = fields.Text(required=True, help="Expression containing a value specification. \n"
                                             "When Formula type is selected, this field may be a Python expression "
                                             " that can use the same values as for the code field on the server action.\n"
diff --git a/odoo/addons/base/models/ir_model.py b/odoo/addons/base/models/ir_model.py
index c441929a3ef..ccceb2c1479 100644
--- a/odoo/addons/base/models/ir_model.py
+++ b/odoo/addons/base/models/ir_model.py
@@ -1201,7 +1201,7 @@ class IrModelConstraint(models.Model):
     definition = fields.Char(help="PostgreSQL constraint definition")
     message = fields.Char(help="Error message returned when the constraint is violated.", translate=True)
     model = fields.Many2one('ir.model', required=True, ondelete="cascade", index=True)
-    module = fields.Many2one('ir.module.module', required=True, index=True)
+    module = fields.Many2one('ir.module.module', required=True, index=True, ondelete='cascade')
     type = fields.Char(string='Constraint Type', required=True, size=1, index=True,
                        help="Type of the constraint: `f` for a foreign key, "
                             "`u` for other constraints.")
@@ -1337,8 +1337,8 @@ class IrModelRelation(models.Model):
 
     name = fields.Char(string='Relation Name', required=True, index=True,
                        help="PostgreSQL table name implementing a many2many relation.")
-    model = fields.Many2one('ir.model', required=True, index=True)
-    module = fields.Many2one('ir.module.module', required=True, index=True)
+    model = fields.Many2one('ir.model', required=True, index=True, ondelete='cascade')
+    module = fields.Many2one('ir.module.module', required=True, index=True, ondelete='cascade')
     write_date = fields.Datetime()
     create_date = fields.Datetime()
 
diff --git a/odoo/addons/test_new_api/models/test_new_api.py b/odoo/addons/test_new_api/models/test_new_api.py
index 3f45466efa3..95a4cec4088 100644
--- a/odoo/addons/test_new_api/models/test_new_api.py
+++ b/odoo/addons/test_new_api/models/test_new_api.py
@@ -266,7 +266,7 @@ class Edition(models.Model):
 
     name = fields.Char()
     res_id = fields.Integer(required=True)
-    res_model_id = fields.Many2one('ir.model', required=True)
+    res_model_id = fields.Many2one('ir.model', required=True, ondelete='cascade')
     res_model = fields.Char(related='res_model_id.model', store=True, readonly=False)