In smart substation, the implementation of anti-maloperation system has heavy workload but low efficiency. This paper presents a method of automatic generating devices' five-prevention rules during the drawing of the main-line diagram for whole substation. The primary equipment graphic objects based on G language could be connected seamlessly to IEC 61850 based model data objects, thus rules files used by anti-maloperation devices could be generated from primary device topology directly, avoiding complicated input configuration of rules database. This method is helpful to increase efficiency and quality of smart substation project implementation.