This article presents data on the distribution of the steppe marmot Marmota bobak Mull, 1776 in the Burtinskaya Steppe Site of the Orenburg State Nature Reserve (Orenburg Region, Belyaevsky District), from its inception to the present. The research was carried out by the author in 1998-2001 and 2021-2022; information on the number of steppe marmots from the archive of the reserve was also used. Mapping of all residential colonies of the steppe marmot and families in them was carried out, and the area of family plots was calculated. Statistical processing of the results of observations was carried out using the STATISTICA 10.0.1011 computer program. The spatial structure of the population, which had developed even before the establishment of the reserve, has been preserved with minor changes for more than 30 years. In the first years (1989-1990), eight relatively small settlements were noted on the territory of the site. Since 1996, ten colonies have been identified, and in 1999, 75 residential family plots were noted on them. By 2003, the territories of the colonies were completely developed, the marmots occupied old abandoned burrows within the colonies, and the number of families on the site increased to 106. Over the next 9 years, the number of families remained stable, after which their number began to decline: by 2017, only 55 families remained. Currently, there is a gradual increase in the number of families in the Burtinskaya Steppe Site; according to the results of mapping in 2022, 74 families were noted.