Abstract: All female young fish, which were produced by mating cruciancarp (Carassius auratus gibelio block)(♀) with common carp (Cyprinus carpio)(scattered ♂) were daily fed on the diet mixed with 95% alcohol (one ml per gramof diet as sex inductive anbstance and 84% of the fish developed into males (sexreversal physiological males). The treatment begun on 16-17 days after hatchingand continued for 30-40 days. After 3 years experiments we got the first asexualgeneration from mating the reversal males with female crucian carp. And then madethe reversal males mate with the first asexual generation, we obtained the secondasexual generation which may be called pure-clonic form of crucian carp. Accordingto the index of morphological characters, numbers of chromosome and the volume ofred cel1, the pureclonic form is not different from crucian carp. Besides, the mecha-nism of sex determination has been found XX (♀);XY (♂).