The western part of the district is located in the Upper Rhine Valley, the eastern part belongs to the northern Black Forest. The highest elevation of the district, the Hornisgrinde (1164 m), is located in the north-east of the district. The lowest elevation (124.3 m) is in the Rhine valley to the north. The district is named after the historical territory of the Ortenau.
The district has a friendship with the Altenburger Land district in Thuringia. Offenburg district already had a city partnership with Altenburg so, after German reunification in 1990, Ortenaukreis chose to help modernize the Altenburger Land administration to the West German standard.