In order to shorten the time of defect elimination and improve the efficiency of defect elimination，the defect elimination of secondary equipment in smart substation usually does not go into seriously the root cause of defects． The defect treatment process is simple and superficial，so that the defects cannot be completely eliminated． Therefore，in order to find out the root cause of defects，the cause of defects is located at the chip level and the principle level，and usually a deep defect detection and analysis for defective equipment is needed． Based on the above reasons，the verification and test methods of defects of secondary equipment in smart substation are studied． A defect verification and testing technique is proposed．