Ramsø was a municipality in the former Roskilde County on the island of Zealand (Sjælland) in east Denmark until 1 January 2007. The municipality covered an area of 76 km2 (29 sq mi) and had a total population in 2005 of 9,320. Its last mayor was Poul Lindor Nielsen, a member of the Social Democrats (Socialdemokraterne) political party. The main town and the site of its municipal council was Viby. Other towns and villages in the municipality were Gadstrup, Skalstrup, Snoldelev and Ørsted.