Sokolov was a member of the 28th Politburo, elected on 14 July 1990 by the 1st Plenary Session of the 28th Central Committee.

From 1944 to the end of the decade he served in the Soviet Army, then worked as a driver on a farm of the Belarusian State Agricultural Academy, where he graduated from in 1956.

In 1969, he became part of the apparatus of the Central Committee and was in 1977 appointed party chief for Brest.

From 6 February 1987 to 30 November 1990, he was First Secretary of the Central Committee of the Communist Party of Belarus, being the last one to serve as the de facto head of the Byelorussian SSR.

Since 1990, he had been a pensioner and continued political activities such as heading the Council of the Communist Party of Belarus.