Storekalsøy or Stora Kalsøy is an island in Austevoll municipality in Hordaland county, Norway. The 6-square-kilometre (2.3 sq mi) island lies northwest of the larger island of Hundvåko and just east of the Marstein Lighthouse. The northern part of the island is very rocky and mountainous. The highest point is the 57-metre (187 ft) tall mountain Mjuken. The smaller islands of Nautøya and Spissøya lies just east of Stora Kalsøy.