Askainen (Villnäs in Swedish) is a municipality of Finland.

It is located in the province of Western Finland and is part of the Varsinais-Suomi region. The municipality has a population of 899 and covers an area of 61,52 km² of which 0,26 km² is water. The population density is 15,099 inhabitants per km².

The municipality is unilingually Finnish.

See also: Municipalities of Western Finland