Until 1 January 2007 Stenlille municipality was a municipality (Danish, kommune) in the former West Zealand County on the island of Zealand (Sjælland) in east Denmark.
The municipality covered an area of 94 km², and had a total population of 5,544 (2005).
Its last mayor was Vagn Guldborg, a member of the Venstre (Liberal Party) political party.
It was merged with existing Sorø and Dianalund municipalities to form the new Sorø municipality.
This created a municipality with an area of 317 km² and a total population of 28,336 (2005).