HJ may refer to:
Hjalmar Horace Greeley Schacht (22 January 1877 – 3 June 1970) was a German economist, banker, liberal politician, and co-founder in 1918 of the German Democratic Party.
Hjalmar "Hjallis" Johan Andersen (12 March 1923 – 27 March 2013) was a speed skater from Norway who won three gold medals at the 1952 Winter Olympic Games of Oslo, Norway.
Hjalmar Peterson was a singer and comedian from Sweden, who achieved great popularity during the 1910s and 1920s.
HJ Bunko (HJ文庫) is a publishing label affiliated with the Japanese publishing company Hobby Japan. It was established in July 2006 and is a light novel label that is aimed at a young adult male readership.
Hjörtur Hermannsson (born 8 February 1995) is an Icelandic professional footballer who currently plays for Brøndby IF as a centre back.
HJ Martin and Son is an interior and specialty contractor based in Northeast Wisconsin. The privately held company has its headquarters in Green Bay and retail locations in Green Bay and Neenah, Wisconsin.