| Rianila River | |
| Map: | Rijeka-Rianila.png |
| Subdivision Type1: | Country |
| Subdivision Name1: | Madagascar |
| Subdivision Type3: | Region |
| Subdivision Name3: | Atsinanana |
| Subdivision Type5: | City |
| Subdivision Name5: | Brickaville |
| Length: | 134km (83miles) |
| Discharge1 Location: | Near mouth |
| Discharge1 Avg: | (Period: 1971–2000)[1] |
| Source1 Location: | Fahona Massif |
| Source1 Elevation: | 1450m (4,760feet) |
| Mouth Location: | Andevoranto, Brickaville, Atsinanana |
| Mouth Coordinates: | -18.9764°N 49.1028°W |
| Mouth Elevation: | 0m (00feet) |
| River System: | Rianila River |
| Basin Size: | 7820km2 |
| Tributaries Left: | Rongaronga |
| Tributaries Right: | Iaroka, Vohitra, |
Rianila is a river in the Atsinanana region in eastern Madagascar. It flows down from the central highlands to flow into the Indian Ocean south of Brickaville at Andevoranto. Its largest tributary is the Rongaronga, which joins it near Brickaville as well as the Iaroka and Vohitra Rivers.
The river was previously called the Iharoka River by Western explorers (and the Jark River in a few sources).[2]