António de Serpa Pimentel (20 November 1825 in Coimbra – 2 March 1900) was Prime Minister of Portugal from 14 January to 11 October 1890. His term in office began as a reaction to the British ultimatum concerning Portuguese colonial policy in southeast Africa. The signing of the Anglo-Portuguese Treaty later that year, which was intended as a step to resolve the crisis, was viewed as further appeasement of a powerful Britain. This led to his resignation and the fall of his government.