Ostrov is a town in the Karlovy Vary Region, Czech Republic. It is located at a foothill of the Ore Mountains about 10 kilometres (6 miles) northeast of Karlovy Vary.

The origin of the settlement named Slávkův ostrov (Slávek’s Island) at the confluence of Bystřice and Jáchymovský Creeks traces back to the beginning of the 13th century. The town charter for Ostrov was issued by Bohemian king John the Blind in 1331.

Ostrov became after World War 2, together with Jáchymov uranium ore processing center. Uranium mining was stopped in 1960.

The extensive housing blocks from the 1950s forming the new part of Ostrov are considered one of the best examples of socialist realism architecture in the Czech Republic.