diff --git a/addons/account/models/account_invoice.py b/addons/account/models/account_invoice.py
index e897f96abd7..ab46cde5838 100644
--- a/addons/account/models/account_invoice.py
+++ b/addons/account/models/account_invoice.py
@@ -1756,14 +1756,14 @@ class AccountInvoiceLine(models.Model):
         result = {}
         if not self.uom_id:
             self.price_unit = 0.0
-        else:
+
+        if self.product_id and self.uom_id:
             if self.invoice_id.type in ('in_invoice', 'in_refund'):
                 price_unit = self.product_id.standard_price
             else:
                 price_unit = self.product_id.lst_price
             self.price_unit = self.product_id.uom_id._compute_price(price_unit, self.uom_id)
 
-        if self.product_id and self.uom_id:
             if self.product_id.uom_id.category_id.id != self.uom_id.category_id.id:
                 warning = {
                     'title': _('Warning!'),