K
- Vasily Kalinnikov, Russian composer (1951)
- Nikolay Karamzin, Russian historian (1991)
- Alexander Karpinsky, geologist (1947)
- Nikolay Kasatkin, Russian painter (1956)
- Sen Katayama, Japanese communist (1967)
- Mstislav Keldysh, mathematician (1981)
- Paul Keres, chess player (1991)
- Aram Khachaturian, composer (1983)
- Mikhail Kharchenko, World War II partisan (1967)
- Kosta Khetagurov, Ossetian poet (1960, 1989)
- Muḥammad ibn Mūsā al-Khwārizmī, Persian astronomer (1983)
- Vasily Kikvidze, revolutionary (1970)
- Viktor Kingissepp, Estonian revolutionary (1950, 1963, 1988)
- Emil Kio, illusionist (1989)
- Orest Kiprensky, Russian painter (1973)
- Vladimir Kistyakovsky, physical chemist (1965)
- Leonid Kizim, cosmonaut (1981, 1985)
- Pyotr Klimuk, cosmonaut (1974)
- Vasily Klyuchevsky, Russian historian (1991)
- Yakub Kolas, Belarusian poet (1957, 1962)
- Alexandra Kollontay, revolutionary (1972)
- Dmitry Komar, 1991 coup d'état attempt victim (1991)
- Vladimir Komarov, cosmonaut (1964)
- Jan Amos Komenský, Czech educationist (1958)
- Komitas, Armenian composer (1969)
- Vera Komissarzhevskaya, Russian actress (1960)
- Maxim Konchalovsky, physician (1975)
- Pyotr Konchalovsky, painter (1976)
- Sergey Konenkov, sculptor (1973)
- Ivan Konev, Marshal of the Soviet Union (1897–1973), issue 1977
- Vladimir Alexeyevich Kornilov, Russian admiral (1989)
- Sergey Korolyov, spacecraft designer (1981, 1982, 1986)
- Oleg Koshevoy, anti-Nazi underground activist (1944)
- Stanislav Kosior, politician (1989)
- Zoya Kosmodemyanskaya, World War II partisan (1942)
- Ivan Kotlyarevsky, Ukrainian writer (1969)
- Sofia Kovalevskaya, Russian mathematician (1951)
- Alexander Kovalevsky, Russian zoologist and embyologist (1951)
- Vladimir Kovalyonok, cosmonaut (1981)
- Sydir Kovpak, World War II partisan (1987)
- Natalya Kovshova, World War II sniper (1944)
- Pyotr Kozlov, Russian explorer (1951)
- Stepan Krasheninnikov, Russian explorer (1951)
- Grigory Kravchenko, aviator (1966)
- Ernst Krenkel, Arctic explorer (1973, 1979)
- Ilya Krichevsky, 1991 coup d'état attempt victim (1991)
- Marko Kropivnitsky, Ukrainian dramatist (1965)
- Nadezhda Krupskaya, revolutionary (1956, 1964)
- Gleb Krzhizhanovsky, revolutionary (1972)
- Ivan Kudrya, intelligence agent (1990)
- Ivan Kulibin, Russian inventor (1955)
- Leonid Kulik, mineralogist (1958)
- Bela Kun, Hungarian revolutionary (1986)
- Yanka Kupala, Belarusian writer (1957, 1962)
- Ivan Kuratov, Komi writer (1989)
- Igor Kurchatov, physicist (1963, 1979)
- Ivan Kuskov, Russian Fort Ross, California settler (1991)
- Boris Kustodiev, painter and stage designer (1978)
- Mikhail Kutuzov, Russian field marshal (1945, 1962)
- Valerian Kuybyshev, politician (1953, 1988)
- Emanuel Kviring, politician (1988)
Read more about this topic: List Of People On Stamps Of The Union Of Soviet Socialist Republics