Larry Mark Christiansen (born June 27, 1956) is an American chess player of Danish ancestry.

In 1971, he became the first junior high-school student to win the National High School Championship.

Christiansen tied for first place with Anatoly Karpov at Linares 1981.

[2] Christiansen played on the United States teams in the Chess Olympiad in 1980, 1982, 1984, 1986, 1988, 1990, 1992, 1996 and 2002.

[3] Christiansen describes his playing style as "aggressive-tactical", and he lists his favorite opening as the Sämisch King's Indian.