Bad Wildungen lies in the eastern foothills of the Kellerwald range in the so-called Waldeck holiday region, 11 km west of Fritzlar, and 35 km southwest of Kassel. The town, which spreads out east of the Homberg, is crossed by the river Wilde, which empties into the Eder at the constituent community of Wega. The constituent communities of Wega and Mandern lie on the Eder, on which also lies the Edersee, a reservoir lying only about 10 km northwest (in a straight line) of the main town of Bad Wildungen. The river Urff flows through the southwest constituent communities of Hundsdorf, Armsfeld and Bergfreiheit.
The nearest large towns are Kassel (about 35 km; northeast), Marburg (about 60 km; southwest) and Korbach (about 28 km; northwest).
Bad Wildungen borders in the north on the community of Edertal (Waldeck-Frankenberg), in the east on the town of Fritzlar, in the southeast on the town of Bad Zwesten (both in the Schwalm-Eder-Kreis), in the south on the community of Haina, and in the west on the town of Frankenau (both in Waldeck-Frankenberg).
Besides the main town, which bears the same name as the whole, the town of Bad Wildungen consists of the centres of Albertshausen, Armsfeld, Bergfreiheit, Braunau, Frebershausen, H�ddingen, Hundsdorf, Mandern, Odershausen, Reinhardshausen and Wega
