diff --git a/addons/mrp/models/mrp_production.py b/addons/mrp/models/mrp_production.py
index b3b936fe7b3..3de5f3d6ca3 100644
--- a/addons/mrp/models/mrp_production.py
+++ b/addons/mrp/models/mrp_production.py
@@ -1306,17 +1306,14 @@ class MrpProduction(models.Model):
 
     def _prepare_stock_lot_values(self):
         self.ensure_one()
-        if self.product_id.tracking == 'lot':
-            name = self.env['ir.sequence'].next_by_code('stock.lot.serial')
-            exist_lot = self.env['stock.lot'].search([
-                ('product_id', '=', self.product_id.id),
-                ('company_id', '=', self.company_id.id),
-                ('name', '=', name),
-            ], limit=1)
-            if exist_lot:
-                name = self.env['stock.lot']._get_next_serial(self.company_id, self.product_id)
-        else:
-            name = self.env['stock.lot']._get_next_serial(self.company_id, self.product_id) or self.env['ir.sequence'].next_by_code('stock.lot.serial')
+        name = self.env['ir.sequence'].next_by_code('stock.lot.serial')
+        exist_lot = self.env['stock.lot'].search([
+            ('product_id', '=', self.product_id.id),
+            ('company_id', '=', self.company_id.id),
+            ('name', '=', name),
+        ], limit=1)
+        if exist_lot:
+            name = self.env['stock.lot']._get_next_serial(self.company_id, self.product_id)
         return {
             'product_id': self.product_id.id,
             'company_id': self.company_id.id,
diff --git a/addons/mrp/tests/test_traceability.py b/addons/mrp/tests/test_traceability.py
index 9bfec2a001e..09c4bbb29d5 100644
--- a/addons/mrp/tests/test_traceability.py
+++ b/addons/mrp/tests/test_traceability.py
@@ -3,6 +3,8 @@
 
 from odoo.tests import Form
 from odoo.addons.mrp.tests.common import TestMrpCommon
+
+from datetime import datetime
 import logging
 
 _logger = logging.getLogger(__name__)
@@ -631,3 +633,21 @@ class TestTraceability(TestMrpCommon):
         mo.action_generate_serial()
         lot_2 = mo.lot_producing_id.name
         self.assertEqual(lot_2, str(int(lot_1) + 1).zfill(7))
+
+    def test_generate_serial_button_sequence(self):
+        """Test if serial in form "00000dd" is manually created, the generate serial
+        correctly create new serial from sequence.
+        """
+        seq = self.env['ir.sequence'].search([('code', '=', 'stock.lot.serial')])
+        seq.prefix = 'xx%(doy)sxx'
+        mo, _bom, p_final, _p1, _p2 = self.generate_mo(qty_base_1=1, qty_base_2=1, qty_final=1, tracking_final='serial')
+
+        # manually create lot_1
+        self.env['stock.lot'].create({
+            'name': "test_000",
+            'product_id': p_final.id,
+            'company_id': self.env.company.id,
+        })
+        # generate serial lot_2 from the MO
+        mo.action_generate_serial()
+        self.assertIn(datetime.now().strftime('%j'), mo.lot_producing_id.name)