Mamerto Urriolagoitía Harriague was a Bolivian lawyer and politician who was the 43rd president of Bolivia, from 1949 to 1951. A member of the Republican Socialist Unity Party, he had previously been the 26th vice president of Bolivia, from 1947 to 1949, under President Enrique Hertzog. Urriolagoitía's short reign was characterized by the violent suppression of the opposition, especially unionists, and he is remembered for his inflexibility. He is considered the last constitutional president of the largely oligarchic social and political order that reigned in the country until the advent of the 1952 Bolivian National Revolution.

The vice president of Bolivia, officially known as the vice president of the Plurinational State of Bolivia, is the second highest political position in Bolivia. The vice president replaces the president in his definitive absence or others impediment and is the ex officio President of the Legislative Assembly.