Abstract: The genetic analysis by spleen graft test was made for three different gynogenetic clones of crucian carp. In three groups of isogenetic graft, the average percentage of individuals with surviving grafts was as high as 95%, This indicated that a majority of individuals of the same gynogenetic clone possessed identical genotype. On the other hand, the grafts between individuals of different gynogenetic clones were rejected within 7 to 14 days (temperature range: 21—30℃). The existence of such gynogenetic clones was therefore demonstrated by means of tissue transplantation. This was in agreement wth the results from genetic marker analysis. The cause for the occasional rejections that occurred in isogenetic grafts was discussed.