Based on the taxonomic composition of taphocoenoses of the main Paleolithic sites of the Anui River Basin within the northwestern Altai Mountains, the structure of mammal communities and potential composition of bioresources of the prehistoric man are reconstructed. It is shown that the basis of communities was composed of medium- and large-sized ungulates, including the Siberian ibex, argali, bison, and horses. A constant and important component of communities was the woolly rhinoceros. The following antelopes are regularly recorded in the Anui Basin: dzeren (Mongolian gazelle) and saiga. Roe deer and Asiatic red deer dwelt everywhere. The Asiatic red deer played a twice greater role than the roe deer as prey of humans. The major elements of communities and main competitors of humans were large carnivores, hyena and wolf. The main competitors in using caves were bear and hyena.