The Hamerský potok (German: Hammerbach) is a stream in the Czech Republic and Germany, a left tributary of the Mže.

It flows mostly through the Plzeň Region in the Czech Republic and briefly also through Bavaria in Germany.

[1] The Hamerský potok originates in the territory of Stará Voda in the Upper Palatine Forest at an elevation of 754 m (2,474 ft) and flows to Kočov, where it merges with the Mže River at an elevation of 442 m (1,450 ft).

[2][3] The longest tributaries of the Hamerský potok are:[4] The Hamerský potok originates in the Czech Republic, flows through Germany between its 25.3 and 29.8 river kilometre, and then continues in the Czech Republic.

[3] The stream flows through the territories of Stará Voda, Mähring, Broumov, Chodský Újezd, Zadní Chodov, Planá, Brod nad Tichou and Kočov.