Alastaro (Finnish pronunciation: [ˈɑlɑstɑro]) is a former municipality of Finland.

It was merged into the town of Loimaa on 1 January 2009.

The municipality had a population of 2,910 (31 December 2008) and covered an area of 258.12 km2 (99.66 sq mi) of which 1.32 km² is water.

The population density was 11.33 inhabitants per km².

This Western Finland location article is a stub.