•
Pyotr Kachura (born 1972), Belarusian footballer •
Pyotr Kakhovsky (1799–1826), Russian Empire officer •
Pyotr Kapitsa (1894–1984), Soviet physicist, engineer, and Nobel laureate •
Pyotr Kapnist (1839–1904), Russian diplomat and ambassador •
Pyotr Karamushko (colonel) (1908–1998), Soviet Red Army colonel •
Pyotr Karatygin (1805–1879), Russian dramatist and actor •
Pyotr Karyshkovsky (1921–1988), Ukrainian Soviet historian, numismatist, scholar, and lexicographer •
Pyotr Kashchenko (1858–1920), Russian psychiatrist, social and agrarian activist, and author •
Pyotr Khanykov (1743–1813), Imperial Russian Navy admiral •
Pyotr Khrustovsky (1979–2003), Russian footballer •
Pyotr Kikin (1775–1834), Russian general and Secretary of State •
Pyotr Kireevsky (1808–1856), Russian folklorist and philologist •
Pyotr Kirillov (1895–1942), Soviet actor, film director, and screenwriter •
Pyotr Pavlovich Kitkin (1877–1954), Russian military commander •
Pyotr Kleinmichel (1789–1869), Imperial Russian Minister of Transport •
Pyotr Klimuk (born 1942), former Soviet cosmonaut and the first Belarusian to travel in space •
Pyotr Kobozev (1878–1941), Russian revolutionary, Soviet statesman and professor •
Pyotr Kochetkov (born 1999), Russian ice hockey goaltender •
Pyotr Kolbasin (born 1942), Russian actor, director, producer, screenwriter •
Pyotr Kolodin (1930–2021), Soviet cosmonaut •
Pyotr Konchalovsky (1876–1956), Russian painter •
Pyotr Koshel (born 1946), Russian writer, historian, and translator •
Pyotr Koshevoy (1904–1976), Soviet World War II officer and later Marshal of the Soviet Union •
Pyotr Kotlyarevsky (1782–1852), Russian general •
Pyotr Kovalenko (1942–1993), Soviet ski jumper •
Pyotr Kozhevnikov (born 1927), Soviet decathlete •
Pyotr Kozlov (1863–1935), Russian and Soviet traveler and explorer •
Pyotr Kozlovsky (1783–1840), Russian diplomat •
Pyotr Krasikov (1870–1939), Russian revolutionary and Communist Party functionary •
Pyotr Krasilov (born 1977), Russian film and theater actor •
Pyotr Krasnov (1869–1947), Russian historian and officer •
Pyotr Krechetnikov (1727–c. 1800), Russian major-general •
Pyotr Krenitsyn (1728–1770), Russian explorer and Imperial Russian Navy officer •
Pyotr Nikolayevich Kropotkin (1910–1996), Soviet Russian geologist, tectonician, and geophysicist •
Pyotr Kryuchkov (1889–1938), Soviet lawyer •
Pyotr Kudryavtsev (1816–1858), Russian writer and historian •
Pyotr Kuryshko (1894–1921), Soviet Russian military commander •
Pyotr Kuznetsov (born 1964), leader and founder of the True Russian Orthodox Church •
Pyotr Kuznetsov (junior sergeant) (1925–1981), Soviet Red Army junior sergeant during World War II and a Hero of the Soviet Union ==L==