Abstract: This paper presents a positive and negative interlocking logical rules automatically checking scheme based on IEC 61850 SSD (System Specification Description) information model. The mainly technology are presented, such as IEC 61850 SSD information model parsing and checking, the analysis about primary equipment and its topology connection relationship for IEC 61850 SSD information model. Loading and checking for interlocking logical rules file. Automatically arranges different logic combinations by the method of automatically generating positive and negative interlocking logical rules. The relationship between the primary equipment topology and the positive and negative interlocking logic is analyzed. The method of association and matching between topological loop and IEC 61850 SSD model is given. The flow of interlocking logical check for operating equipment such as disconnector, circuit breakers, ground disconnector,earthing switch is designed. Automatically check substation interlocking logic based on IEC61850 SSD information model is realized. Substation typical interlocking logic case is used for verifying the correctness of the method about automatically check interlocking logic.