| Sâi | |
| Name Other: | Șiu |
| Pushpin Map: | Romania |
| Subdivision Type1: | Country |
| Subdivision Name1: | Romania |
| Subdivision Type2: | Counties |
| Subdivision Name2: | Olt, Teleorman |
| Length: | 85km (53miles) |
| Mouth: | Danube |
| Mouth Coordinates: | 43.7149°N 24.8503°W |
| Basin Size: | 314km2 |
The Sâi (also: Șiu) is a left tributary of the river Danube in Romania. It discharges into the Danube near Turnu Măgurele.[1] It flows parallel to the lower course of the river Olt, about 5 km east of the Olt, through the villages Dăneasa, Sprâncenata, Beciu, Plopii-Slăvitești, Slobozia Mândra, Uda-Clocociov, Saelele, Lunca, Segarcea-Vale and Lița. Its length is 85km (53miles) and its basin size is 314km2.