Marais Viljoen, DMS (2 December 1915 – 4 January 2007) was the last ceremonial State President of South Africa from 4 June 1979 until 3 September 1984.

He was married on 20 April 1940 to Dorothea Maria Brink (17 September 1917 – 5 October 2005), with whom he had one daughter Elizabeth Magdalena (Elna) Viljoen.

After finishing school at Jan van Riebeeck High School in Cape Town, he went to work in the Post Office, and thereafter at the Afrikaans language newspaper, Die Transvaler, edited by Hendrik Verwoerd, who later became prime minister.

[2] After Vorster's resignation as a result of the Muldergate Scandal in 1979, Viljoen held the post of non-executive State President from 4 June 1979 until 3 September 1984.

After Viljoen had retired from public life, he continued to maintain an interest in politics.