Niedersimmental District is one of the 26 administrative districts in the canton of Bern, Switzerland. From 1 January 2010, the district lost its administrative power while being replaced by the Frutigen-Niedersimmental (administrative district), whose administrative centre is Frutigen. As of 2010, it remains therefore a fully recognised district under the law and the Constitution (Art.3 al.2) of the Canton of Berne. Its capital, while having administrative power, was the municipality of Wimmis. The district had an area of 319 km2 and consisted of 9 municipalities: