Birender Singh Thapa was an Indian light-flyweight boxer who was active during the late 1970s and early 1980s. Thapa boxed at the 1978 Commonwealth Games in Edmonton, Canada, winning bronze after losing to the eventual gold medallist Steve Mushioki in the semi-finals. In recognition of his achievement he was bestowed with the Arjuna Award by the government of India in 1979. The following year he boxed at the 1980 Moskva Olympics but lost his first bout to Dietmar Geilich to be eliminated from the tournament. Thapa then won a bronze medal at the 1981 Kings Cup in Thailand before competing at his second Commonwealth Games when he boxed in Brisbane in 1982.