Râu Sadului is a commune located in Sibiu County within the Transylvania region of Romania. Situated at the foothills of the Cindrel Mountains, it is positioned approximately 30 kilometers south of the county capital, Sibiu.
The commune consists of a single village also named Râu Sadului and is situated within the Mărginimea Sibiului ethnographical area. According to the 2011 census, the population of the commune was composed entirely of ethnic Romanians.