was an Amt ("collective municipality") in the district of Rendsburg-Eckernförde, in Schleswig-Holstein, Germany. It was named after the lake Wittensee, which is situated in the Amt. It was located between Eckernförde and Rendsburg. The village Groß Wittensee was the seat of the Amt. In January 2008, it was merged with the Amt Wittensee to form the Amt Hüttener Berge. The Amt Wittensee consisted of the following municipalities: Borgstedt Bünsdorf Groß Wittensee Haby Holtsee Holzbunge Klein Wittensee Neu Duvenstedt Sehestedt Former Ämter in Schleswig-Holstein