diff --git a/addons/mrp/mrp.py b/addons/mrp/mrp.py
index 23033fa0af5..f5b6cf466a5 100644
--- a/addons/mrp/mrp.py
+++ b/addons/mrp/mrp.py
@@ -325,8 +325,8 @@ class mrp_bom(osv.osv):
                 })
             else:
                 bom_id = self._bom_find(cr, uid, bom_line_id.product_uom.id, product_id=bom_line_id.product_id.id, properties=properties)
-                bom2 = self.browse(cr, uid, bom_id)  
-                if bom2:
+                if bom_id:
+                    bom2 = self.browse(cr, uid, bom_id)  
                     res = self._bom_explode(cr, uid, bom2, bom_line_id.product_id, factor,
                         properties=properties, level=level + 10, previous_products=all_prod, master_bom=master_bom)
                     result = result + res[0]