Rittmarshausen is a nucleated village in the municipality (Gemeinde) Gleichen in the district Göttingen, Germany. The village of 776 residents (as of December 31, 2005) is primarily agricultural and home of people working in Göttingen. "Ökozentrum Rittmarshausen" is an association dedicated to the development and marketing of regionally produced natural foods, which are marketed under the Leinehöfe label.