This study established a multiplex STR genotyping system through universal fluorescent primers in combination with sequencing.For each panel of multiplex STR genotyping amplification,two sets of primers were used,namely universal primers labeled with FAM and specific primers with an added 5' tail.We optimized the proportion of universal and specific primers and reaction of multiplex PCR was achieved.By using this method,five STR marker loci genotyping were successfully conducted within a single reaction.The optimized universal fluorescent primers amplification genotyping system can be used in multiplex STR genotyping,which allows reliable,effective and low-cost genotyping compared with regular microsatellite fluorescent detection assays.