Thornhill Park is a suburb in Melbourne, Victoria, Australia, 32 km west of Melbourne's Central Business District, located within the City of Melton local government area. Thornhill Park recorded a population of 3,066 at the 2021 census. The suburb was gazetted by the Office of Geographic Names on 9 February 2017, following a proposal for eleven new suburbs by the City of Melton. The new name officially came into effect in mid-2017.