Revillagigedo Island is an island in the Alexander Archipelago in Ketchikan Gateway Borough of the southeastern region of the U.S. state of Alaska. Running about 89 km north-south and 48 km east-west, it is 2,754.835 km² in area, making it the 12th largest island in the United States and the 167th largest island in the world. Its center is located near 55°38′03″N 131°17′51″W.
The island is separated from the Alaska mainland to the east by Behm Canal, from Prince of Wales Island to the west by the Clarence Strait, and from Annette Island to the south by Revillagigedo Channel and Nichols Passage. The island is traditional Tlingit territory, and by the nineteenth century was divided between the Saanyaa Ḵwáan and Taantʼa Ḵwáan tribes or subdivisions. The first European recorded as having sighted it was Spanish explorer Jacinto Caamaño in 1792; it was named the following year by George Vancouver for Juan Vicente de Güemes, 2nd Count of Revillagigedo, then viceroy of New Spain.
The island's population was 13,950 as of the 2000 census.