Analysis of the geographic extent of faunas in the Carboniferous seas of USSR has provided general characters for defining biogeographic provinces in the area. Two provinces are distinguished in the lower and middle Carboniferous seas. The Europe-Tien Shan province is divided into regions including the Ukraine-Donets, eastern USSR, Ural, Transcaucasus, and Tien Shan regions. The Kazakhstan-Siberia province includes the regions of Kazakhstan, Altai, Kuznetsk basin, Transbaikalia, Taimyr, Kolyma-Koryak, Mongolia, Sikhote-Alin. In the upper Carboniferous, following a major regression, the differences between the marine faunas of Europe and Central Asia increased to such a degree that the corresponding basins must be considered independent provinces--eastern Europe, Tien Shan, eastern Siberia, and the Pacific Ocean. The data presented are based on published material.