Donji Lapac is a town in the middle of the Lapacko Field in the south-eastern part of Lika, 27 km east of Udbina. It comprises the hamlets of Bujadnice and Zbjeg Lapacki. Economy is based on farming, livestock breeding, wood-processing and textile industry. Donji Lapac is located at the intersection of the main road Knin - Bihac and regional roads D. Lapac - Udbina and D. Lapac - Bjelopolje.

A habitation existed here already in Roman times. The old town of Lapac was located on an isolated hill called -Obljaj, which rises in the Lapacko Field, south of the town.