Ulstein is a municipality in Møre og Romsdal county, Norway. It is part of the Sunnmøre region. The commercial and administrative centre of Ulstein is the town of Ulsteinvik, with a population of 6,033 people (2013). The municipality occupies the western half of the island of Hareidlandet, as well as about 30 or more smaller islands, four of which are populated.