Nguyễn Bá Cẩn was a South Vietnamese politician who served as the penultimate Prime Minister of South Vietnam from 4 April 1975 until 28 April 1975, serving under Presidents Nguyễn Văn Thiệu and Trần Văn Hương. Before becoming prime minister, he was a member of the lower house of the National Assembly representing Định Tường province and served as the second Speaker of the lower house.