Loket (Czech pronunciation: [ˈlokɛt]; German: Elbogen) is a town in Sokolov District in the Karlovy Vary Region of the Czech Republic. It has about 3,100 inhabitants. The town is known for the Loket Castle, a 12th-century Gothic castle. The historic town centre is well preserved and is protected as an urban monument reservation.

Loket consists of four municipal parts (in brackets population according to the 2021 census):

Both Loket and Elbogen mean "elbow" in Czech and German, respectively. The town got its name due to the town centre being surrounded on three sides by the Ohře River, and the shape the river takes is similar to that of an elbow.

Loket is located about 6 kilometres (4 mi) east of Sokolov and 8 km (5 mi) southwest of Karlovy Vary. It lies mostly in the Slavkov Forest, only the northwestern part of the town extends into the Sokolov Basin. The highest point is the hill Zelenáč at 707 m (2,320 ft) above sea level. The Ohře River flows through the town.

In the second half of the 12th century, a royal castle Loket was built on a landmark promontory within the Ohře River bend. It used to be called the "Key to the Kingdom of Bohemia". Soon after, a small town, first mentioned in 1234, arose below the castle.

In the early 15th century the royal town was fortified and turned into an important focal point of the Bohemian Crown. In the course of the 19th century, the town became famous for its local porcelain factory. However, industrial production was located in the surrounding towns.

From 1938 to 1945, Loket was occupied by Nazi Germany and administered as part of the Reichsgau Sudetenland. In 1945, the German population was expelled according to the Beneš decrees. In the late 20th century, the castle underwent a complete reconstruction and was subsequently open to the public.

Loket is the starting point of the railway line to Chomutov.