Sir William Charles Windeyer (29 September 1834 – 11 September 1897) was an Australian politician and judge. As a New South Wales politician he was responsible for the creation of Belmore Park (north of the new Central railway constructed in 1874 in Haymarket), Lang Park (in Church Hill, between York, Lang and Grosvenor Streets in the city), Observatory Park (on Flagstaff Hill in the west Rocks) and Cromwell Park at the head of Long Bay, Malabar and parks on Clark, Rodd, and Snapper Islands. He was also the author of the New South Wales Patents Act and the Married Women's Property Act of 1879.