Sunnylven is a former municipality in Møre og Romsdal county, Norway. The 637-square-kilometre (246 sq mi) municipality existed from 1838 until its dissolution in 1965. Since that time, it has made up the southern part of the present-day Stranda Municipality. It encompassed the areas around the Sunnylvsfjorden and Geirangerfjorden. The village of Hellesylt was the administrative centre of the municipality and Geiranger was the other main population centre in Sunnylven. The main church for the municipality was Sunnylven Church in Hellesylt.