diff --git a/addons/delivery/models/sale_order.py b/addons/delivery/models/sale_order.py
index 0f0adfa07ce..532d1360f0a 100644
--- a/addons/delivery/models/sale_order.py
+++ b/addons/delivery/models/sale_order.py
@@ -150,6 +150,7 @@ class SaleOrderLine(models.Model):
     def _compute_product_qty(self):
         for line in self:
             if not line.product_id or not line.product_uom or not line.product_uom_qty:
+                line.product_qty = 0.0
                 continue
             line.product_qty = line.product_uom._compute_quantity(line.product_uom_qty, line.product_id.uom_id)