Background. The European bison (Bison bonasus) is the only wild ox of Europe, survived to our days. Whilst numerous studies have been undertaken to characterize the Lowland line of European bison, it is little known about allele pool and population genetic structure of the Lowland-Caucasian line of wisent. Materials and methods. The samples were collected from twenty-six animals of Russian breeding nucleus of Lowland-Caucasian line. Ten Bos Taurus microsatellites (TGLA227, BM2113, ETH10, SPS115, TGLA122, INRA23, TGLA126, BM1818, ETH225, and BM1824) were used for analysis. Results. Eight of ten microsatellite loci (excluding TGLA227 and INRA23) were polymorphic. The number of alleles per locus is varied of one to five with average value of 2.80 ± 0.47. The alleles, which are specific for Lowland-Caucasian line, were identified. We observed relatively high inbreeding level (FIS = 0,091) and very low effective population size (Ne = 1.8, 95% CIs, Parametric 1.1-2.9). We showed that two genetically distinct groups have taken part in formation of allele pool of studied wisent population. Conclusion. Our data indicated that the development of breeding program to decrease the inbreeding degree and to increase the level of genetic diversity is necessary.