This paper mainly starts with the four representative standards of plugs and sockets such AS IEC60884,BS 1363,AS/NZS 3112 and UL 817,and research the assessment methods of plugs and Flexible cables and their connec-tion in each standard,focusing on the comparison of the method differences between different standards,and research the design of each test method,The influencing factors in the testing process,the unqualified case analysis and other aspects are studied.