Karlsruhe is a Landkreis (district) in the northwest of Baden-Württemberg, Germany.

Neighboring districts are (from north clockwise) Rhein-Neckar, Heilbronn, Enz, Calw, Rastatt, Germersheim, Rhein-Pfalz-Kreis and the district-free city Speyer.

In 1809 it was split into one part responsible for the city Karlsruhe (Stadtamt), and one for the surrounding municipalities (Landamt).

The western part of the district is located in the Rhine valley.

The area in the east belongs to the landscape of the Kraichgau, and it is also to the north of the foothills of the Black Forest.