diff --git a/addons/account/report/account_invoice_report.py b/addons/account/report/account_invoice_report.py
index 7559fe68361..eb2a8633c78 100644
--- a/addons/account/report/account_invoice_report.py
+++ b/addons/account/report/account_invoice_report.py
@@ -92,7 +92,7 @@ class AccountInvoiceReport(models.Model):
                 move.invoice_date_due,
                 uom_template.id                                             AS product_uom_id,
                 template.categ_id                                           AS product_categ_id,
-                line.quantity / NULLIF(COALESCE(uom_line.factor, 1) / COALESCE(uom_template.factor, 1), 0.0)
+                line.quantity / NULLIF(COALESCE(uom_line.factor, 1) / COALESCE(uom_template.factor, 1), 0.0) * (CASE WHEN move.move_type IN ('in_invoice','out_refund','in_receipt') THEN -1 ELSE 1 END)
                                                                             AS quantity,
                 -line.balance                                               AS price_subtotal,
                 -line.balance / NULLIF(COALESCE(uom_line.factor, 1) / COALESCE(uom_template.factor, 1), 0.0)
diff --git a/addons/account/tests/test_account_invoice_report.py b/addons/account/tests/test_account_invoice_report.py
index fe4327d5b30..92009dd8522 100644
--- a/addons/account/tests/test_account_invoice_report.py
+++ b/addons/account/tests/test_account_invoice_report.py
@@ -112,7 +112,7 @@ class TestAccountInvoiceReport(AccountTestInvoicingCommon):
             [1000,           1000,           1],
             [1000,           1000,           3],
             [6,              6,              1],
-            [-20,            -20,            1],
-            [-20,            -20,            1],
-            [-600,           -600,           1],
+            [-20,            -20,           -1],
+            [-20,            -20,           -1],
+            [-600,           -600,          -1],
         ])