Finnøy is an island in Finnøy municipality in Rogaland county, Norway. The 25-square-kilometre (9.7 sq mi) island is one of the largest in the island municipality. The administrative centre, Judaberg, is located on the eastern shore of the island. The island is located on the southern side of the Boknafjorden, about 20 kilometres (12 mi) northeast of the city of Stavanger. The village of Hesby, on the western coast, is a historical seat of power dating back to the Middle Ages. Hesby is also the site of Hesby Church which dates back to around the year 1100.