The nature of regional zoning of the prevalence of dirofilariasis in Russia was first established and a map reflecting the structure of an area with the identification of three zones (low, moderate, and stable transmission risks) was drawn up. In Russia, natural and climatic conditions are favorable for the development of transmitting mosquitoes and larvae of Dirofilaria to the invasion stage in the body of the transmitter to the south of the latitude of 58 degrees north in the European part and Western Siberia and to the south of the latitude of 50 degrees north in the Far East. The region of dirofilariasis covers 53 subjects of the Russian Federation, in 39 subjects (including 29 in the European part and 10 in the Asian part) of which 564 cases of dirofilariasis were notified in 1915-2008. 68.44% of dirofilariasis cases were registered in the endemic area in 11 subjects of the Russian Federation in the stable transmission risk zone while in the moderate and low transmission risk zones these amounted to 31.55% in 28 subjects. Information on the area of dirofilariasis is needed to estimate its incidence in man in different regions of Russia, which will assist in diagnosing this zoogenous transmissible helminthiasis.