Malachi is a Jewish prophet in the Bible.
Malachi or Malachai is also the given name of:
- Malachi ben Jacob HaKohen (1695/70?–1772), Talmudist, methodologist and Kaballist
- Malachi Bogdanov, British theatre director
- Malachi Curran, politician in Northern Ireland
- Malachi Cush (born 1980), Northern Irish singer/songwriter
- Malachi Davis (born 1977), American sprinter
- Malachi Dupre (born 1995), American football player
- Malachi Favors (1927–2004), American jazz bassist
- Malachi Fields, American football player
- Malachi Flynn (born 1998), American basketball player
- Malachi Jones (born 1989), Bermudian cricketer
- Malachi Jones (clergyman) (c.1651–1729), Anglo-Welsh clergyman and missionary
- Malachi Jones (American football) (born 1994), American football player
- Malachi Kittridge (1869-1928), American Major League Baseball catcher
- Malachi Leo Elliott (1886–1967), American architect
- Malachi Martin (1921–1999), Catholic priest, writer and commentator
- Malachi Martin (Australian murderer) (c.1831–1862)
- Malachi Martin (politician) (1822–?), American politician
- Malachi Nelson (born 2004), American football player
- Malachi O'Doherty (born 1951), journalist, author and broadcaster in Northern Ireland
- Malachi Ritscher (1954–2006), American human rights and anti-war activist and musician
- Malachi Singleton (born 2004), American football player
- Malachi Thompson (1949–2006), American jazz trumpet player
- Malachi Throne (1928-2013), American actor
- Malachi Wideman (born 2001), American football player