diff --git a/addons/account/tests/common.py b/addons/account/tests/common.py
index 7ecfbeda403..50743012fc5 100644
--- a/addons/account/tests/common.py
+++ b/addons/account/tests/common.py
@@ -379,7 +379,7 @@ class AccountTestInvoicingCommon(TransactionCase):
         for product in (products or []):
             with move_form.invoice_line_ids.new() as line_form:
                 line_form.product_id = product
-                if taxes:
+                if taxes is not None:
                     line_form.tax_ids.clear()
                     for tax in taxes:
                         line_form.tax_ids.add(tax)
@@ -388,7 +388,7 @@ class AccountTestInvoicingCommon(TransactionCase):
             with move_form.invoice_line_ids.new() as line_form:
                 line_form.name = "test line"
                 line_form.price_unit = amount
-                if taxes:
+                if taxes is not None:
                     line_form.tax_ids.clear()
                     for tax in taxes:
                         line_form.tax_ids.add(tax)