George Marsden Waterhouse was a Premier of South Australia from 8 October 1861 until 3 July 1863 and the seventh premier of New Zealand from 11 October 1872 to 3 March 1873.

The premier of South Australia is the head of government in the state of South Australia, Australia. The Government of South Australia follows the Westminster system, with a Parliament of South Australia acting as the legislature. The premier is appointed by the governor of South Australia, and by modern convention holds office by virtue of their ability to command the support of a majority of members of the lower house of Parliament, the House of Assembly.