José Maria de Mascarenhas Relvas de Campos (Golegã, Golegã, 5 March 1858 – Alpiarça, Casa dos Patudos, 31 October 1929; Portuguese pronunciation: [ʒuˈzɛ ˈʁɛlvɐʃ], was a Portuguese politician and Prime Minister of Portugal.

An historic republican, he proclaimed the republic from the balcony of the Municipal Chamber of Lisbon, on 5 October 1910.

He was the second Minister of Finance during the provisional government led by Teófilo Braga, from 12 October 1910 to 3 September 1911.

He was President of the Ministry (Prime Minister), from 27 January to 30 March 1919, in one of the many short-lived governments of the Portuguese First Republic.

[1] His house in Alpiarça is now a museum, the Casa dos Patudos, where his art collection is exhibited, which consists of over 13,000 glass negatives.