John Spencer (10 August 1946 – 18 February 2021) was an Australian professional rugby league footballer who played in the 1960s and 1970s.
Spencer made his debut for Balmain in 1966 but was not a member of the side which reached the grand final that year.
In 1969, Spencer was a part of the Balmain side which defeated Souths 11–2 at the Sydney Cricket Ground.
This would prove to be the last premiership Balmain would win as a stand-alone entity before merging with the Western Suburbs Magpies to form the Wests Tigers at the end of 1999.
After some of the Balmain stars had retired or moved on, Spencer stayed with the club and captained the side during the early 1970s.