Præstø is a town with a population of 3,821 (1 January 2015) and a former municipality (Danish, kommune) in Vordingborg Municipality in Region Sjælland on the east coast of the island of Zealand (Sjælland) near its southwestern tip in south Denmark. The former Præstø municipality included the islands of Maderne, Storeholm, and Lilleholm which lie in Præstø Fjord. The former municipality covered an area of 107 km², and had a total population of 7,608 (2005). Its last mayor was Ole Møller Madsen, a member of the Venstre (Liberal Party) political party.
The islands of Maderne, Storeholm and Lilleholm are part of the Præstø Fjord Wildlife reserves (Præstø Fjord Vildtreservat).
As of January 1, 2007, Præstø municipality ceased to exist as the result of Kommunalreformen ("The Municipality Reform" of 2007). It was merged with existing Langebæk, Møn, and Vordingborg municipalities to form an enlarged Vordingborg municipality. This created a municipality with an area of 615 km² and a total population of 46,307 (2005). The municipality belongs to the new Region Sjælland ("Zealand Region").