Аннотация:The available information on differentiation of the Kamchatka Parasalmo (Oncorhynchus) mykissrainbow trout populations by microsatellite DNA loci were clarified. Using both traditional estimations of genetic differentiation (common and pairwise FST-statistics) and Bayesian clustering methods, the population genetic relationships of the species were determined in the Kamchatka region. It was confirmed that the isolation of Kamchatka rainbow trout populations is confined to large river basins in Western and Eastern Kamchatka. It was noted that the rainbow trout from the Zhupanova River (Eastern Kamchatka), as well as the samples from the Kvachina and Utkholok rivers (Western Kamchatka), are the most isolated by microsatellite loci.