The Sebeș (Hungarian: Sebes, German: Mühlbach) is a left tributary of the river Mureș in Transylvania, Romania. The upper reach of the river (upstream of Lake Oașa) is also known as Frumoasa. The Romanian and Hungarian name Sebeș and Sebes originate from the Hungarian adjective sebes meaning "speedy", while the German name means Mill Creek. The source of the river is on the south slope of the Cindrel Mountains, in the southwestern part of Sibiu County. It discharges into the Mureș in Alba Iulia.