Sir Robert Dove Nicholls (27 June 1889 – 18 January 1970) was an Australian politician who represented the South Australian House of Assembly seats of Stanley from 1915 to 1938 and Young from 1938 to 1956 for the Liberal and Country League and party predecessors. He was one of the two members for Stanley for the entire time it was a two-member seat, and the member for Young for its entire existence. He served a record period as Speaker of the South Australian House of Assembly from 1933 to 1956.