Abstract:Genetic relationship between white spot pike (Esox lucius) in Eltrix River and black spot pike (Esox reicherti) in Helongjiang River in China was studied by random amplified polymorphic DNA (RAPD) technique. (1) Using 34 effective primers, in white spot pike population, totally 257 bands were obtained, in which 130 bands were polymorphic, average bands per primer was 7.56, the percentage of polymorphic loci was 50.58% . In black spot pike population, totally 267 bands were obtained, in which 135 bands were polymorphic, average bands per primer was 7.85, the percentage of polymorphic loci was 50.56%. There was no significant difference between these two pikes in the percentage of polymorphic loci (P > 0.05). (2) Primer S68 produced a monombrphic band with molecular weight 1943bp in black spot pike population, but not in white spot pike -population. Therefore, 1943bp of S68 could be considered as a genetic marker to distinguish these two pikes. (3) Between the two species of pike, genetic similarity, genetic distance was 0.8090 and 0.0125 respectively. Within species, the genetic similarity for the white spot pike was 0.8171, black spot pike was 0.8213; the genetic distance for the white spot pike was 0.1829, far black spot pike was 0.1787; the Shannon' 8 index of genetic diversity for the white spot pike was 0.1236, for black spot pike was 0.1241, and there was no significant difference between these two pikes in above 3 indexes.