Keysborough is a suburb in Melbourne, Victoria, Australia, 27 km south-east of Melbourne's central business district. Its local government area is the City of Greater Dandenong. In 2014, Keysborough had an estimated population of 22,800.Keysborough includes market gardens and semi-rural properties and is also a large residential/industrial suburb which started to grow in the 1960s and well into the 1990s. The Post Office opened on 27 November 1973 and was known as Noble Park South until 1978.