diff --git a/base_jsonify/models/models.py b/base_jsonify/models/models.py
index 14e00e103..ad1abf803 100644
--- a/base_jsonify/models/models.py
+++ b/base_jsonify/models/models.py
@@ -72,9 +72,9 @@ class Base(models.AbstractModel):
                     if value is False and field_type != 'boolean':
                         value = None
                     elif field_type == "date":
-                        value = fields.Date.to_string(value)
+                        value = fields.Date.to_date(value).isoformat()
                     elif field_type == "datetime":
-                        value = fields.Datetime.to_string(value)
+                        value = fields.Datetime.to_datetime(value).isoformat()
                     res[json_key] = value
             result.append(res)
         return result
diff --git a/base_jsonify/tests/test_get_parser.py b/base_jsonify/tests/test_get_parser.py
index 5aea2d55f..fc08952bd 100644
--- a/base_jsonify/tests/test_get_parser.py
+++ b/base_jsonify/tests/test_get_parser.py
@@ -70,7 +70,7 @@ class TestParser(TransactionCase):
                     'country_id': self.env.ref('base.fr').id
                 })
             ],
-            'date': fields.Date.today()
+            'date': fields.Date.from_string("2019-10-31")
         })
         expected_json = {
             'lang': 'en_US',
@@ -96,8 +96,8 @@ class TestParser(TransactionCase):
                 'name': 'Sebatien Beau',
                 'email': None
             }],
-            'create_date': fields.Datetime.to_string(partner.create_date),
-            'date': fields.Date.to_string(partner.date)
+            'create_date': partner.create_date.isoformat(),
+            'date': "2019-10-31"
         }
         json_partner = partner.jsonify(parser)