Gundsømagle is a town located two kilometres east of Jyllinge and Roskilde Fjord in the northern part of Roskilde Municipality, approximately 40 kilometres west of Copenhagen, Denmark.

Gundsømagle is mentioned (as Guthensø; 1376 Gundesiø maklæ) in a letter from Bishop Absalon where he grants the village to Æbeæholt Abbey which was founded on the small island of Eskilsø in Roskilde Fjord.

When the monastery moved to its new home in North Zealand, it kept some of its old holdings.

It was confiscated by the Crown in connection with the Reformation and the land was sold off in lots to private buyers in 1670.

The village began to grow in the 1960s and was selected as seat of the new Gundsø Municipality which was created in 1970 from a portion of Sømme herred, Gundsømagle Church dates from about 1100.