 Mittenaar borders in the north on the community of Siegbach, in the northeast on the community of Bischoffen, in the east on the community of Hohenahr, in the southeast on the town of Aßlar, in the south on the community of Ehringshausen, in the southwest on the community of Sinn, and in the west on the town of Herborn (all in the Lahn-Dill-Kreis).The community consists of the centres of Ballersbach, Bellersdorf, Bicken (administrative seat) and Offenbach.The community of Mittenaar came into being on 1 January 1972 with the merger of the formerly independent municipalities of Ballersbach, Bicken and Offenbach.