Robert Campbell Begg MC (11 April 1886 – 26 July 1971) was a New Zealand medical doctor and politician who served as the president of the conservative New Zealand Legion from 1933 until 1934–35. Born in New Zealand and educated in Scotland, Begg then served in World War I. He returned to New Zealand after completing his education, going on to serve in the leadership of the New Zealand Legion in the years before its dissolution. He also wrote a series of medical textbooks.

He was born in Dunedin on 11 April 1886. He first studied theology and then studied medicine at the University of Edinburgh, qualifying MB ChB. After serving as a medical officer during World War I, for which he was awarded the Military Cross. His service included treating Indian soldiers in Flanders and Egyptian soldiers during the Gallipoli campaign. He then returned to Edinburgh, gaining an MD in 1923.

Begg was the president of the New Zealand Legion from 1933 until 1935. In 1935, Begg was awarded the King George V Silver Jubilee Medal. During his tenure as President of the Legion, Begg was approached by the Nazis as a potential fascist political organization, but he rebuked the Nazis, reportedly calling their ideology 'absurd'. In 1937, Begg moved with his family to South Africa.

Begg died on 26 July 1971, in Johannesburg, South Africa; he was survived by his five children.