| Honorific-Prefix: | The Honourable |
| John McMahon | |
| Order: | Minister for Lands |
| Premier: | Joseph Cahill Bob Heffron |
| Term Start: | 1 April 1959 |
| Term End: | 31 May 1960 |
| Predecessor: | William Gollan |
| Successor: | Jack Renshaw |
| Order1: | Minister for Transport |
| Premier1: | Bob Heffron Jack Renshaw |
| Term Start1: | 31 May 1960 |
| Term End1: | 13 May 1965 |
| Predecessor1: | George Enticknap |
| Successor1: | Milton Morris |
| Order2: | Alderman of the Balmain Municipal Council |
| Term Start2: | 5 December 1942 |
| Term End2: | 2 December 1944 |
| Predecessor2: | Michael McMahon |
| Constituency2: | South-West Ward |
| Birth Date: | 1914 2, df=yes |
| Birth Place: | Hobart, Tasmania, Australia |
| Death Place: | Sydney, New South Wales, Australia |
| Party: | Labor |
| Allegiance: |  Australia |
| Branch: | Australian Army |
| Serviceyears: | 1943–1945 |
| Rank: | Lance Sergeant |
| Unit: | Royal Australian Engineers 2/11 Australian Army Transport Company |
| Battles: | Second World War |
John Michael Alfred McMahon (21 February 1914 – 19 May 1975) was an Australian politician and a member of the New South Wales Legislative Assembly from 1950 until 1968. He was a member of the Labor Party and held ministerial positions including Minister for Transport and Minister for Lands.[1]
McMahon was born in Hobart, Tasmania and was the son of, Michael Hubert McMahon (d. 1942), a clerk who later became the Mayor of Balmain. He was educated at the Christian Brother's, Rozelle and was employed as a store manager for Coles & Co. He served in the Second Australian Imperial Force in the Engineers' Corps from 1943 to 1945 and reached the rank of Lance Sergeant.[2] He later ran a delicatessen in Rozelle and was a member of the shop assistants' union. He was elected as an alderman on Balmain Municipal Council between 1942 and 1944, when the council was composed entirely of Labor councillors. His father was mayor before he joined the council, and McMahon filled his place on the council at a December 1942 by-election.[3] [4] [5]
McMahon entered the New South Wales Parliament at the 1950 state election as the labor member for Balmain. He defeated the sitting Labor member Mary Quirk who had lost her party endorsement. McMahon was a member of the governments of Joseph Cahill, Robert Heffron and Jack Renshaw. He was appointed as a Minister without portfolio in 1957 and became the first Minister for Lands in 1959.
In 1960 he was commissioned as the Minister for Transport and he held this position until the defeat of the Labor government at the 1965 election. He retained his seat and retired at the 1968 election. He died age 61 in 1975 and was buried at Field of Mars Cemetery, East Ryde, following a service at St Joseph's Church, Rozelle.[6]