Abstract: The haemoglobin and four different isozymes were analysed in erythrocytes ofsilver crucian carp, Carassius auratus gibclio and red common carp,Cyprinus carpio red variety,and their hybrid,the multiple tetraploid allogynogenetic cruciancarp,C. auratus,using polyacrylalmide gradient gel electrophoresis technique.Someloci(Hb、EST、SOD)in multiple tetraploid allogynogenetic crucian carp expressednot only the maternal but also the paternal genes.Some bands appeared which isnot original in silver crucian carp,and some original bands in silver crucian carpwere repressed.It is thus indicated that the multiple tetraploid allogynogeneticcrucian carp exhibited features of a hybrid,and that isozyme gene expressions ofthe allogynogenetic crucian carp should be much closer to the silver crucian carpfrom the analyses of phenotypes of four different isozymes.