Abstract: The similarities and differences of amplified DNA fragments among themultiple species of silver crucian carp, allogynogenetic silver crucian carp and redcommon carp (Cyprinus carpio) were analysed through the RAPD technique optimizedin this system.Forty random primers of 10 nucleotide long sequence were used in theRAPD analysis.Generally, there existed similar amplified products between themultiple species and allogynogenetice silver crucian carp, whereas most of the productswere obviously different in red common carp.The similarity of the amplified DNAbands between the multiple species and red common carp was 31.6%, and thesimilarity between allogynogenetic silver crucian carp and red common carp was28.6%.Some amplified DNA bands were discovered to be shared by the multiple species, allgynogenetic silver carp and red common carp, and some bands wererevealed to be shared between the multiple species and red common carp.Moreover,a few of specific bands were found only in the multiple species.The results not onlyprovided new molecular evidences for incorporation of heterologous genetic materialsin the multiple species, but also demonstrated that heterologous genetic materials inthe multiple species were more than that in allogynogenetic silver crucian carp.