The paper presents data on the variants of human immunodefficiency virus type 1 (HIV-1) currently circulating in Russia. The subtype A HIV-1 variant dominating is shown to be most widespread among drug-injected users in the most regions under study. By using the results of an analysis of 1,464 blood samples taken in the past 4 years in 69 subjects of the Russian Federation, the authors have estimated that this HIV-1 variant is responsible for 93% of all HIV-infection cases in the country. The greatest regional genetic diversity was observed in Moscow and its mean (2.35(1.59) was found to be comparable to that (2.41(1.85) in the whole country. Penetration of the subtype A IV-1 variant early detectable among drug-users into other risk groups was noted.