The Harmanliyska reka (Bulgarian: Харманлийска река) is a river in southern Bulgaria, a right tributary of the Maritsa.

The river drains the eastern slopes of the Mechkovets ridge, the northern slopes of the ridges Chukata and Huhla, and large areas of the Haskovo hills, all part of the Eastern Rhodope Mountains.

[1][2] The river takes its source from the Velichka spring at an altitude of 755 m, situated near the second class II-58 road Asenovgrad–Kardzhali some 1.5 km west of the Panichkovo resort in the Eastern Rhodope Mountains.

Downstream of the village of Malevo the Harmanliyska reka turns in northeastern direction and after Stoykovo it bends eastwards, bypassing the Huhla ridge from the north in a valley with steep slopes on the right bank and oblique slopes on the left one.

[1][2] Its drainage basin covers a territory of 956 km2 or 1.8% of the Maritsa's total and borders the drainage basins of the Banska to the north and northwest, the Biserska reka to the southeast and the Arda to the southwest, all of them right tributaries of the Maritsa.