The Leibstadt Nuclear Power Plant is located in the municipality Leibstadt (canton Aargau, Switzerland) on the Rhine River close of the Aare delta and the German border. It is so far the last nuclear power station built in Switzerland.

A boiling water reactor built there by the company General Electric with 1,220 MW of electrical power serves the power demands of the area, the cooling is done via a cooling tower. The nuclear power station has produced approximately 8.5 TWh per year, slightly less than the power station Gösgen.

The Leibstadt Nuclear Power Plant is owned by Leibstadt AG (KKL), which is composed of six Swiss energy companies: the Aare Tessin AG for electricity (Atel) with 27%, the northeast power stations AG (NOK) with 23%, the central-Swiss power stations AG (CKW) with 14%, the electricity company running castle AG (EGL) with 16%, the Bern power stations AG (BKW FMB energy AG) with 10% and the Aargauer of power stations AG (AEW energy AG) with 5 %. The management was originally done by the EGL, but with establishment of the Axpo it was consolidated within the Axpo group, so whereby today the NOK is the manager. The plant also houses a 380 kV switchyard for Beznau.

The Leibstadt Nuclear Power Plant is an old project, planning began 1964 for a 600 MW reactor with river water cooling. With the prohibition of the river water cooling by the Swiss Federal Council in 1971 a cooling tower solution was favored. In the further planning process the output was increased to 600 and then 900 MW. In 1984 the plant started after an eleven-year construction period. After the Three Mile Island accident in the year 1979 new safety regulations were implemented, and the completion was delayed several years. While the budget was originally set for 2,000,000,000 Swiss francs, and the end of construction it had amounted to over 5,000,000,000 francs.

The history of the completion of the KKL reflected increasingly critical attitudes toward Nuclear power in Switzerland during the 1970s and 1980s, which culminated in the resistance the Kaiseraugst Nuclear Power Plant.