The agency was appointed to the business following a pitch against Bartle Bogle Hegarty and Smith Dennison.
DDB's first work for the brand will launch in Spring 2011, and will include TV, cinema, print, outdoor, radio and experiential activity.
Gü first called a review of its advertising business in September. Previously the chocolate brand had worked with Mother London on a project basis.
Gü’s most recent advertising campaign launched in March, and introduced the new strapline: "Gü you Ganache?"
The campaign included a Twin-Peaks-style TV ad, created by Mother, which featured a middle-aged woman visiting a dark and seedy underworld to get her first taste of Gü.
Gü currently sells a range of chilled chocolate puddings and brownies. It also offers a range of fruit-based desserts, which are sold under the name Frü.