Oulunsalo is former municipality in the region of Northern Ostrobothnia, in Finland. It was founded in 1882 and merged into the city of Oulu on 1 January 2013, along with Haukipudas, Kiiminki and Yli-Ii. The municipality had a population of 9,746 and covered an area of 211.22 square kilometres, of which 127.86 km2 is water. Its population density was 116.915/km2. Oulu Airport is located in Oulunsalo.