Keith "Huffer" Christiansen (born july 14, 1944 in Fort Frances, Ontario) is a former professional ice hockey player who appeared in 138 World Hockey Association regular season games with the Minnesota Fighting Saints between 1972 and 1974.
Before turning professional, Christiansen was a member of the United States's 1972 Winter Olympics team that won the silver medal and also played for the United States at the 1970 and 1971 World Championships.
Christiansen played for the University of Minnesota-Duluth from 1963 to 1967. He also played with the Waterloo Black Hawks and Grand Rapids Bruins of the United States Hockey League as an amateur.
In the WHA he played in 138 games and scored 23 goals and 55 assists,
Christiansen was inducted into the United States Hockey Hall of Fame in 2005.