Patrick John Murdoch (10 June 1850 – 1 June 1940) was a Scottish-Australian Presbyterian minister, known for being the father of Keith Murdoch and the grandfather of Rupert Murdoch.
Murdoch was born in Aberdeenshire, and studied at the University of Aberdeen and New College, Edinburgh before being ordained as a minister of the Free Church of Scotland. In 1884, he emigrated to the Colony of Victoria with his parents (James and Helen Murdoch) and his wife Annie.
After three years at West Melbourne Presbyterian Church, Murdoch was called to Trinity Church, Camberwell, where he served from 1887 to 1928. He also served as moderator of the Presbyterian Church of Victoria in 1898-99 and moderator general of the Presbyterian Church of Australia in 1905-06.
Murdoch was also Clerk of the Presbytery of Melbourne South in from 1896 to 1920. During the Ronald v. Harper slander and libel case in 1909, he refused to produce a letter which was in the presbytery's possession, and spent a night in gaol for contempt of court. William Gray Dixon suggested in 1930 that this incident demonstrated how the Presbyterian Church of Australia "maintains her traditional spirit of independence".