Sergey Timofeyevich Konenkov was a Russian and Soviet sculptor. He was often called "the Russian Rodin".

Sergey Nikolayevich Krivenko was a Russian journalist, publicist and editor associated with the Narodnik movement. In the 1870s and early 1880s he was one of the prominent figures in Otechestvennye Zapiski where, starting form 1881 he was the editor of the Internal Affairs review section.

Sergey Yervandovich Kurginyan is a Russian politician, scientist, and theatre producer. He is the founder and leader of the Russian ultraconservative neo-Soviet movement Essence of Time.

Sergey Olegovich Kuznetsov is a Russian historian and art historian, specialising in the history of the Stroganov family.

Sergey Yurievich Kuznetsov is a contemporary Russian writer, journalist, entrepreneur and educator.

Sergey Georgiyevich Lazo was a Russian nobleman, officer of the Imperial Russian Army, and Bolshevik leader in the October 1917 Revolution in the Russian Far East.

Sergey Alekseyevich Lebedev was a Soviet scientist in the fields of electrical engineering and computer science, and designer of the first Soviet computers.

Sergey Danilovich Lugansky was a flying ace in the Soviet Air Forces during the Second World War who was twice awarded the title Hero of the Soviet Union for having gained at least 34 solo shootdowns during the war.

Count Sergei Lvovich Levitsky, is considered one of the patriarchs of Russian photography and one of Europe's most important early photographic pioneers, inventors and innovators.

Sergey Konstantinovich Makovsky was a Russian Empire poet, art critic, and organiser of many exhibitions of modern art.