Alexey

Alexey, Alexei, Alexie, or Aleksie (Алексей ; Алексей ), is a Russian and Bulgarian male first name deriving from the Greek Aléxios (Αλέξιος), meaning "Defender", and thus of the same origin as the Latin Alexius.

Alexey may also be romanized as Aleksei, Aleksey, Alexej, Aleksej, etc. It has been commonly westernised as Alexis.

Similar Ukrainian and Belarusian names are romanized as Oleksii (Олексій) and Aliaksiej (Аляксей), respectively.

The Russian Orthodox Church uses the Old Church Slavonic version, Alexiy or Aleksiy (Алексiй, or Алексий in modern spelling), for its Saints and hierarchs (most notably, this is the form used for Patriarchs Alexius I and Alexius II). The name became fairly popular in Russia after the baptism of Michael of Russia's son, Alexis of Russia.

The common hypocoristic is Alyosha (Алёша) or simply Lyosha (Лёша). These may be further transformed into Alyoshka, Alyoshenka, Lyoshka, Lyoha, Lyoshenka (Алёшка, Алёшенька, Лёшка, Лёха, Лёшенька, respectively), sometimes rendered as Alesha/Aleshenka in English. The form Alyosha may be used as a full first name in Bulgaria (Альоша) and Armenia.

In theory, Alexia is the female form. It is, however, almost non-existent in Russian-speaking countries. A popular Russian, Ukrainian, and Belarusian female name Olesia/Olesya/Alesia/Alesya is one possible form.

The patronymics based on Alexey are Alexeyevich (male) and Alexeyevna (female).

The following surnames derive from Alexey and its various forms:
 * Alexeyev/Alekseyev
 * Alexeyevsky
 * Alyoshin
 * Alyokhin (Alekhine, Alekhin)
 * Lyoshin
 * Alexeytsev/Alekseytsev /Alekseitsev
 * Alexeychuk/Alekseychuk/Alekseichuk
 * Alexeychik/Alekseychik/Alekseichik
 * Alexeyuk/Alekseyuk
 * Alexeyenko/Alekseyenko/Alekseenko
 * Alexeychenko/Alekseychenko/Alekseichenko
 * Alexievich

Alexeyevka is a common Russian village name.

People known by first name Alexey and variants

 * Alexis of Russia, Tsar of Russia from 1645 to 1676, son of Tsar Michael
 * Aleshenka, a rumored alien found in Russia
 * Grand Duke Alexei Alexandrovich of Russia, son of Tsar Alexander II
 * Alexey Andreevich Anselm, Russian theoretical physicist
 * Alexei Berestnev (born 1991), Russian ice hockey player
 * Alexei Cherepanov (1989–2008), Russian hockey player
 * Alexei A. Efros, American computer scientist
 * Alexei L. Efros, American physicist
 * Alexey Goloborodko, Russian dancing contortionist
 * Alexey Goncharuk (Oleksiy Honcharuk), former Ukrainian prime minister
 * Aleksi Inauri (1908–1993), Soviet Georgian commander who headed the Georgian KGB
 * Alexei Ivanov (disambiguation), several people
 * Alexey Karamazov, fictional character from Fyodor Dostoyevsky's The Brothers Karamazov
 * Alexei Kovalev, Russian professional ice hockey player
 * Aleksei Yevgenyevich Kravchenko, Russian actor
 * Aleksey Kuleshov, Russian volleyball player
 * Alexei Leonov, pioneering Russian cosmonaut, first person to conduct a space walk
 * Alexei Makeyev (born 1991), Russian ice hockey player
 * Grand Duke Alexei Mikhailovich of Russia, grandson of Tsar Nicholas I
 * Alexei Navalny (1976–2024), Russian politician
 * Alexei Nemov, Russian Olympic gymnast
 * Alexei Nikolaevich, Tsarevich of Russia, the son of Nicholas II of Russia and Alexandra Feodorovna (Alix of Hesse) and younger brother of Grand Duchess Anastasia Nikolaevna of Russia
 * Alexey Pajitnov, inventor of the popular puzzle game Tetris
 * Tsarevich Alexei Petrovich of Russia, son of Peter I the Great
 * Alexei Ponikarovsky, Ukrainian-Canadian professional ice hockey player
 * Alexei Ramírez, Cuban baseball player
 * Alexey Rykov, Bolshevik revolutionary and Soviet politician
 * Alexei Savrasov, Russian artist
 * Alexei Sayle, English comedian and author
 * Alexei Shirov, Latvian-Spanish chess Grandmaster
 * Alexey Shved, Russian basketball player
 * Alexey Sorokin (disambiguation), several people
 * Aleksei Sytsevich, fictional character in the Marvel universe, better known as Rhino
 * Alexei Tezikov (1978–2020), Russian ice hockey player
 * Alexey Vishnya, Russian musician
 * Alexei Yagudin, Russian figure skater