diff --git a/addons/stock/wizard/stock_return_picking.py b/addons/stock/wizard/stock_return_picking.py
index 29b83d9200f..97a1a4c5bd2 100644
--- a/addons/stock/wizard/stock_return_picking.py
+++ b/addons/stock/wizard/stock_return_picking.py
@@ -142,7 +142,7 @@ class stock_return_picking(osv.osv_memory):
                 move_obj.copy(cr, uid, move.id, {
                     'product_id': data_get.product_id.id,
                     'product_uom_qty': new_qty,
-                    'product_uos_qty': uom_obj._compute_qty(cr, uid, move.product_uom.id, new_qty, move.product_uos.id),
+                    'product_uos_qty': new_qty * move.product_uos_qty / move.product_uom_qty,
                     'picking_id': new_picking,
                     'state': 'draft',
                     'location_id': move.location_dest_id.id,