Balbir Singh Kullar played hockey for India at the 1968 Mexico City Olympics, winning a bronze medal. He was also on the 1964 Indian Olympic hockey squad, but did not play at Tokyo. He made his début on the national team in 1963 in Lyon, France, starring with them as an inside forward. He helped India win the 1966 Asian Games gold medal in Bangkok.
Domestically Singh Kullar played for Punjab Police, and worked as a deputy inspector-general with the police. He also played briefly for Railways. In 1999 Singh Kullar was given the Arjuna Award for his service with the police. He died in February 2020 from a heart attack.