Liane Marianne Tooth, OAM (born 13 March 1962 in Sydney, New South Wales) is a retired field hockey forward, who twice won the gold medal with the Australian Womens Hockey Team, best known as the Hockeyroos, at the Summer Olympics: in Seoul (1988) and in Atlanta, Georgia (1996).

Tooth was the first female hockey player to compete in four Olympic Games (1984 to 1996). She began playing field hockey at school in Sydney. Since 1994 she has devoted much of her professional life to increasing sporting opportunities and physical activity, particularly for girls and women; for the Active Women unit of the WA Department of Sport and Recreation. Most recently she has been working for the same department as an Officiating and Coaching Consultant, helping to develop officials such as referees and judges, and coaches.

She was inducted into the Sport Australia Hall of Fame in 1996. She was one of the eight flag-bearers of the Olympic Flag at the opening ceremony of the 2000 Summer Olympics in Sydney, New South Wales, Australia.