Studies of an isolated Ileksko-Kozhozersky group of European forest reindeer (Rangifer tarandus fennicus Lönnberg 1909) of the easternmost part of range in Fennoscandia were carried out in 2008-2009, 2011 and 2016-2019. The results of the study showed that the named reproductive group is quite stable in the last decade and has about 250-300 individuals. In the autumn period, the share of yearlings in herds is 13-14%, that fully compensates for the natural death from predators and not significant poaching in this part of the range. Due to the lack of sufficient areas of lichen forest types in this territory, reindeers do not form winter concentrations. They move in small groups (9.6 ± 0.9 individuals) in large forest-bog complexes, feeding mainly on epiphytic lichen species. This feature prevents the active pursuit of animals by poachers and contributes to the stability of the group. Reindeers practically do not go beyond the intact taiga massif during the winter movements, each herd during this season uses vast territories with an area of up to 2000 km2. The main danger to the existence of reindeer in the study area is the reduction of the habitat as a result cutting of old coniferous forests.