An analysis of polymorphism of the fragment of the control region of mitochondrial DNA of 53 tissue samples of the brown bear Ursus arctos from several regions of the eastern part of Russia was carried out. It was found that most of the described haplotypes belong to cluster 3a, the most common in Eurasia, and do not form regionally specific haplogroups. However, among the bears from Western and Eastern Siberia, as well as the island of Kunashir, three haplotypes were identified, which are close to the haplogroup typical of Eastern Hokkaido bears. The assumption was made of the existence in Siberia and the Far East of one or more Pleistocene refugia.