Cellulose acetate membr ane and SDS -polyacr ylamide gel elect rophoresis wer e used to compare the serum components among crucian car p and several stra ins of goldfishes (gold cr ucian , gr ass goldfish , r ed wen goldfish , red dr agon-eye goldfish and red oval goldf ish )from China .Furthermore , these str ains wer e analysed by dual immune dif fusion and convect ive immune elect rophoresis in which ant i-crucian car p serum f rom rabbi t was used .The r esults are as follows :⑴ The serum components and an tigenicity of cr ucian car p and these st rains of goldf ishes are similar in a high degr ee .⑵ It is demonst rated that there ar e some differences in these fishes by the analysis of electrophore tic gr ams and the determination with highly eff icient ant i-serum.These dif ferences conside rably are consistent with the evolut ionary posit ions among these fishes .