Sheriff Mustapha Dibba (10 January 1937, Salikene, Central Baddibu – 2 June 2008) was a veteran Gambian politician who was the First Vice President and also served as the country's National Assembly speaker from 2002 to 2006. He was also leader of the National Convention Party (NCP).
Dibba was the son of Mustapha Dibba, a Mandinka chief. He was educated at Armitage School and from 1955 to 1957 at the Methodist Boys High School in Bathurst. He worked as a clerk for the United Africa Company before resigning in 1959 to work for the recently formed People's Progressive Party. There he organized the party's youth wing and was elected to the House of Representatives as representative for Baddibu in the 1962 election.
Dibba was the Gambia's first vice-president. He resigned from that position in 1975 and later formed the National Convention Party (NCP). Following elections in 1977, the NCP became the main opposition party in the Gambia.
He was incarcerated in 1981 for alleged involvement in the foiled coup attempt that year, but was freed after 11 months in detention. A presidential election was held on 4 May 1982, months after a constitutional amendment instituting direct election of the country's head of state. Dibba was defeated by incumbent President Dawda Jawara. He ran again as the NCP presidential candidate in 1987 and 1992, placing second to Jawara both times.