Masku (Finnish pronunciation: [ˈmɑsku]) is a municipality of Finland.

The Swedish name no longer has official status, and is considered outdated according to the Institute for the Languages of Finland.

[6] The people of Masku also once held hunting grounds in the Turku archipelago, as evidenced by the toponym Maskinnamo (originally *Maskun Innanmaa) in Korpo.

The most famous resident of Masku is Finnish tennis player Jarkko Nieminen.

Baron C. G. E. Mannerheim, field marshal and 6th President of Finland was born in Louhisaari Manor of Askainen in 1867.