Abstract:The mitochondrial DNAs (mtDNAs) of Carassius auratusbeZia,arassas auratus cuiera and Carassius auratus auratus Were digested by thirteenrestriction endonucleases, Via..Bam HI, Eco RI,13ra I,I,Hird III,Hpa TT,Msr I,Pst IAI, rna I, Xba I,I and rfaZ I. The double enzyme digestions wereconducted by using Bam HI, Eco RI, d III, Sma I, a I, SL I and Pst I. Thefragments Were obtained and their molecular sixes Were estimated. by aga.rase geIelectrophoresis. The size of mtDNAs for C. aecratusbeZin, C. auratus ceaiera and C.anratus auratusare 1599±90bp, 1600±130bp and 15540±140bp respectively.Taexperimental results demonstrated that the electrophoretic patterns of mtDNAsfor C. au-atusgibeaa, C. auratus cxiera and C. duratus aurdtus obtained by eithersingle or double enzyme digestion were significantly different, and the patternsof C. auraEusbebwv were obviously different among individuals by using Ha II.Besides, the restriction maps of mtDNAs from above species rere constructed byusing Bam HI, Pst I, Ecv RI and Xba I.