Sergey Vladimirovich Aleksashenko is a Russian economist and former government official. He was the deputy finance minister and first deputy chairman of the board of the Central Bank of Russia from 1995 to 1998.

Sergei A. Alexandrovsky is a Ukrainian poet and translator who writes in Russian language.

Sergei Sergeyevich Alexeyev was a Soviet and Russian legal scholar and politician. He was the first and only chairman of the Committee for Constitutional Supervision of the USSR from 1990 to 1991. Later, he was one of the co-authors of the Constitution of Russia of 1993, along with Anatoly Sobchak and Sergey Shakhray.

Sergei Amanovich Khummedov, better known by the pen name Sergei Aman, is a Russian writer and journalist.

Sergei Chernyshev, born 4 August 1952, Bohodukhiv, Kharkiv Oblast, Ukrainian Soviet Socialist Republic is a Russian philosopher, educator and expert in the field of organization and management science.

Sergei Vladimirovich Bakhrushin was Russian Soviet historian, medievalist and university professor.

Sergei Vasilevich Beletsky Сергей Васильевич Белецкий was a Russian archaeologist and historian. He was a Doctor of Historical Sciences and Leading Researcher of the Department of Slavic-Finnish Archeology for the Institute of the History of Material Culture of the USSR Academy of Sciences (RAS).

Sergei Aleksandrovich Bershadski was a Russian Empire historian and jurist.

Sergei Nikolayevich Bulgakov was a Russian Orthodox theologian, priest, philosopher, and economist. Orthodox writer and scholar David Bentley Hart has said that Bulgakov was "the greatest systematic theologian of the twentieth century." Father Sergei Bulgakov also served as a spiritual father and confessor to Mother Maria Skobtsova.

Sergei Aleksandrovich Buturlin ; 22 September 1872 in Montreux – 22 January 1938 in Moscow was a Russian ornithologist. He was a pioneer in Russia of the study of the diversity of species and described more than 200 new species of bird.