John Joseph Gregory McGirr (11 October 1879 – 23 March 1949) was an Australian politician who served in the New South Wales Legislative Assembly from 1913 to 1925, representing the Labor Party. He served as the party's leader (and Leader of the Opposition) for little over a month in 1923, during an internal dispute. He had earlier served as deputy leader and as Minister for Public Health under James Dooley.
