Kjersti Østgaard Buaas (born 5 January 1982) is a Norwegian snowboarder from Trondheim.
She placed 4th in women's half-pipe at the 2002 Winter Olympics in Salt Lake City, United States.
She received a bronze medal at the 2006 Winter Olympics in women's half-pipe in Turin, Italy.
Buaas recovered from a broken leg only a week before her bronze-winning ride.
In 2007/2008 she finished World No.3 on the Swatch TTR World Snowboard Tour (Ticket to Ride (World Snowboard Tour))