Háj u Duchcova (German: Haan) is a municipality and village in Teplice District in the Ústí nad Labem Region of the Czech Republic. It has about 1,400 inhabitants. Háj u Duchcova lies approximately 8 kilometres (5 mi) west of Teplice, 24 km (15 mi) west of Ústí nad Labem, and 79 km (49 mi) north-west of Prague.