Kislau concentration camp, also known as KZ Kislau in German, was a concentration camp operating in Nazi Germany from 21st April 1933 until 1st April 1939.

Kislau concentration camp was located in Kislau castle in the state of Baden-Württemberg. Before turning into a concentration camp, Kislau castle saw many changes in purpose. In 1721, when it was originally built, it was used as a hunting lodge. Decades later in 1813 it was repurposed into a hospital and military casern. In 1824 Kislau castle became a state prison and a workhouse, with the workhouse being housed inside the Kislau castle. Finally in 1933, after the Nazis seized power, part of Kislau castle was made into a concentration camp.

Unlike most concentration camps, Kislau was overseen by Baden Interior Ministry instead of CCI. Kislau functioned mostly as a concentration camp for political prisoners as well as a re-education camp. Ludwig Marum, a socialist parliament member, was murdered in Kislau by SA and SS forces in 1934. After the closing of Kislau concentration camp in 1939, the prisoners were transported to Dachau concentration camp.

After being closed, Kislau prison and workhouse continued functioning in the Nazi era. In 1940 two of Himmler's representatives inspected the site to see if it could be utilised as a concentration camp, but the plan was never fulfilled. In spring 1944, after two prisons, Mannheim prison and Saarbrücken prison, were badly damaged in allied air raids, Kislau prison became a place to hold the inmates of the two prisons.

Nowadays the Kislau castle has a memorial stone in memory of the victims of the Holocaust.

49°12′58″N 8°38′40″E / 49.2160°N 8.6445°E / 49.2160; 8.6445