Leonid (Russian: Леонид [lʲɪɐˈnʲit]; Ukrainian: Леонід [leoˈn⁽ʲ⁾id]; Belarusian: Леанід, romanized: Ljeaníd [lʲɛaˈnʲit]) is a Slavic version of the given name Leonidas. The French version is Leonide.

People with the name include:

• Leonid Agutin (born 1968), Russian pop musician and songwriter
• Leonid Andreyev (1871–1919), Russian playwright and short-story writer who led the Expressionist movement in the national literature
• Leonid Brezhnev (1906–1982), leader of the USSR from 1964 to 1982
• Leonid Buryak (b. 1953), USSR/Ukraine-born Olympic-medal-winning soccer player and coach
• Leonid Bykov (1928–1979), Soviet and Ukrainian actor, film director, and script writer
• Leonid Desyatnikov (b. 1955), Soviet and Russian opera and film composer
• Leonid Feodorov (1879–1935), a bishop and Exarch for the Russian Catholic Church, and survivor of the Gulag
• Leonid Filatov (1946–2003), Soviet and Russian actor, director, poet, and pamphleteer
• Leonid Gaidai, (1923–1993), Soviet comedy film director
• Leonid Geishtor (b. 1936), USSR (Belarus)-born Olympic champion Canadian pairs sprint canoer
• Leonid Gobyato (1875–1915), Russian lieutenant-general and designer of the modern, man-portable mortar
• Leonid Hurwicz (1917–2008), Russian-born American economist and mathematician who shared the 2007 Nobel Prize in Economics
• Leonid Ivanov (disambiguation), several people
• Leonid Kadeniuk (1951–2018), first and only astronaut of independent Ukraine to fly into outer space
• Leonid Kharitonov (singer) (1933–2017), Soviet and Russian bass-baritone singer
• Leonid Khrushchev (1917–1943), missing aviator
• Leonid Kogan (1924–1982), Soviet and Russian violinist
• Leonid Kantorovich (1912–1986) Soviet and Russian mathematician, economist, and only winner from the USSR of the Nobel Prize in Economics
• Leonid Kolumbet (1937–1983), Soviet and Ukrainian Olympic cyclist
• Leonid Kostandov (1915–1984), Soviet politician
• Leonid Krasin (1870–1926), Soviet and Russian engineer and politician
• Leonid Kravchuk (1934–2022), Ukrainian politician and first President of Ukraine
• Leonid Krupnik (b. 1979), Ukrainian-born American-Israeli former soccer player and current soccer coach
• Leonid Kuchma (b. 1938), second President of Ukraine
• Leonid Kuravlyov (1936–2022), Soviet and Russian actor
• Leonid Levin (b. 1948), Soviet-American computer scientist
• Leonid Fyodorovich Myasin, French transliteration: Léonide Massine (1896–1979), Russian choreographer and ballet dancer
• Leonid Mezheritski (1930–2007), Soviet and Israeli still-life, portrait and landscape painter
• Leonid Moseyev (b. 1952), Soviet and Russian long-distance runner
• Leonid Pasternak (1862–1945), Russian Impressionist painter
• Leonid Reiman (or Reyman) (b. 1957), Russian businessman and government official, currently Minister of Communications and Information Technologies of the Russian Federation
• Leonid Rozhetskin, (1966–20??), Russian-American financier and lawyer who disappeared in 2008; remains found in 2013
• Leonid Sagayduk (1929–1998), Soviet swimmer
• Leonid Sigal, Russian violinist and conductor
• Leonid Sobinov (1872–1934), Russian opera singer
• Leonid Stadnyk (1970–2014), Ukrainian man named "world's tallest living man" by Guinness World Records 2008
• Leonid Stein (1934–1973), Soviet Grandmaster chess player from Ukraine among the top ten players in the 1960s
• Leonid Taranenko (b. 1956), 1980 Olympic weightlifting champion for the Soviet Union
• Leonid Teyf, Russian-Israeli businessman
• Leonid Toptunov (1960–1986), reactor control engineer killed in the Chernobyl disaster
• Leonid Utyosov (Leyzer (Lazar) Vaysbeyn, or Weissbein) (1895–1982), Soviet and Russian jazz singer and comic actor
• Leonid Volkov (b. 1980), Russian opposition politician, IT specialist, Alexei Navalny аssociate
• Leonid Voskresensky (1913–1965), Soviet rocket engineer and launch director for Sputnik
• Leonid Yakubovich (b. 1945), Russian television host
• Leonid Zhabotinsky (1938–2016), Soviet weightlifter and Olympic gold medalist

Fictional characters include:

• Leonid, the protagonist in Alexander Bogdanov’s 1908 Russian science fiction novel Red Star
• Leonid, the protagonist in the Labyrinth trilogy of cyberpunk novels written in the late 1990s by Russian science fiction writer Sergei Lukyanenko (Labyrinth of Reflections, False Mirrors, and Transparent Stained-Glass Windows).
• Leonid Gorbovsky, in Arkady and Boris Strugatsky's series of science fiction novels set in the Noon Universe
• Leonid Kovar, Russian superhero also known as Red Star
• Leonid McGill, Manhattan private detective in fiction written by Walter Mosley
• Leonid Pavel, Russian nuclear scientist in The Dark Knight Rises