diff --git a/addons/product/product.py b/addons/product/product.py
index 0d1ee6f47d9..c8688991700 100644
--- a/addons/product/product.py
+++ b/addons/product/product.py
@@ -524,8 +524,7 @@ class product_packaging(osv.osv):
 		'ul_qty' : fields.integer('UL by layer'),
 		'rows' : fields.integer('Number of layer', required=True,
 			help='The number of layer on palette'),
-		'product_id' : fields.many2one('product.product', 'Product',
-			select=1, required=True),
+		'product_id' : fields.many2one('product.product', 'Product', select=1, ondelete='cascade', required=True),
 		'ean' : fields.char('EAN', size=14,
 			help="The EAN code of the transport unit."),
 		'code' : fields.char('Code', size=14,