Kristjan is a masculine given name in the Estonian language and Slovenian language. It is a variation of the name Christian. Notable people named Kristjan include:
Kristjan Čujec (born 1988), Slovenian futsal player
Kristjan Fajt (born 1982), Slovenian professional road bicycle racer
Kristjan Gregorič (born 1989), Slovenian track cyclist
Kristjan Glibo (born 1982), German football defender and manager
Kristjan Ilves (born 1996), Estonian Nordic combined skier
Kristjan Järvi (born 1972), Estonian-American conductor
Kristjan Niels Julius (1860–1936), Icelandic-American satirical poet
Kristjan Kais (born 1976), Estonian beach volleyball player
Kristjan Kaljurand (born 1992), Estonian male badminton player
Kristjan Kangur (born 1982), Estonian basketball player
Kristjan Kitsing (born 1990), Estonian basketball player
Kristjan Lipovac (born 1989), Slovenian football goalkeeper
Kristjan Makke (born 1981), Estonian basketball player
Kristjan Palusalu (1908–1987), Estonian heavyweight wrestler
Kristjan Jaak Peterson (1801–1822), Estonian poet
Kristjan Prendi (born 1997), Albanian footballer
Kristjan Rahnu (born 1979), Estonian decathlete
Kristian Rand (born 1987), Estonian ice dancer
Kristjan Raud (1865–1943), Estonian painter and drawer
Kristjan Sarv (born 1979), Estonian actor, director and contemporary artist
Kristjan Sokoli (born 1991), American football defensive end