The Dreta is a river in Styria, northeastern Slovenia. The river is 29 km (18 mi) long.
Its source is near the Črnivec Pass in the Kamnik Alps. It flows through the town of Gornji Grad, Bočna, and Šmartno ob Dreti, and merges with the Savinja River in Nazarje. The Dreta Valley (Slovene: Zadrečka dolina) is named after the river.
