Sir (John) Mostyn Hanger KBE (3 January 1908 – 11 August 1980) was a judge in Queensland, Australia.

He won a scholarship to attend and study at the University of Queensland where he obtained a Bachelor of Arts in 1929.

[1] He married Greta Lumley Robertson at St Andrew's Presbyterian Church in Brisbane on 8 April 1936.

[1] Hanger enlisted in the Royal Australian Air Force on 25 May 1942 and became a flight lieutenant.

[1] After leaving University, he obtained a position as a clerk in the Supreme Court of Queensland.

[1] A decision in which he ruled against re-employing forty five men by Mount Isa Mines led to an unsuccessful attempt to remove him from the court.

His son John Mostyn Hanger, born on 21 June 1937, followed in his footsteps and became a Judge of the District Court of Queensland, serving in that role from 1976 to 1993.

[8] Hanger was appointed a Knight Commander of the Order of the British Empire (KBE) in 1973.