| Jiu | |
| Map: | Raul Jiu.png |
| Map Size: | 270 |
| Subdivision Type1: | Country |
| Subdivision Name1: | Romania |
| Subdivision Type2: | Counties |
| Subdivision Name2: | Hunedoara, Gorj, Dolj |
| Subdivision Type3: | Cities |
| Subdivision Name3: | Petroșani (Jiul de Est), Lupeni (Jiul de Vest), Târgu Jiu, Craiova |
| Length: | 340km (210miles) |
| Discharge1 Location: | mouth |
| Discharge1 Avg: | 86m3/s |
| Source1: | Confluence of headwaters Jiul de Vest and Jiul de Est, near Petroșani, Hunedoara |
| Source1 Coordinates: | 45.3686°N 23.3678°W |
| Source1 Elevation: | 554m (1,818feet) |
| Mouth: | Danube |
| Mouth Location: | near Bechet, Dolj |
| Mouth Coordinates: | 43.7781°N 23.8133°W |
| Basin Size: | 10080km2 |
| Tributaries Left: | Jiul de Est, Gilort, Amaradia |
| Tributaries Right: | Jiul de Vest, Motru |
The Jiu (in Romanian; Moldavian; Moldovan ʒiw/; Hungarian: Zsil in Hungarian pronounced as /ʒil/; German: Schil or Schiel; Latin: Rabon) is a river in southern Romania. It is formed near Petroșani by the confluence of headwaters Jiul de Vest and Jiul de Est.
It flows southward through the Romanian counties Hunedoara, Gorj, Mehedinți and Dolj before flowing into the Danube near Zăval,[1] a few kilometers upstream from the Bulgarian city of Oryahovo. It is long, including its source river, Jiul de Vest. It has a basin of 10430km2.[2] Its average discharge at the mouth is .
The upper Jiu Valley, around Petroșani and Lupeni, is Romania's principal coal mining region.
The following towns are situated along the Jiu, from source to mouth: Petroșani (Jiul de Est), Lupeni (Jiul de Vest), Bumbești-Jiu, Târgu Jiu, Turceni, Filiași, and Craiova.
The following rivers are tributaries of the Jiu (from source to mouth):