| Deduru Oya | |
|---|---|
 Aerial view of the mouth of Deduru River, Chilaw. | |
  | |
| Physical characteristics | |
| Source | |
| • location | Kurunegala District |
| Mouth | |
• location | Chilaw |
• coordinates | 07°36′50″N 79°48′12″E / 7.61389°N 79.80333°E |
• elevation | Sea level |
| Length | 142 km (88 mi) |
| Basin size | 2,620 km2 (1,010 sq mi) |
The Deduru Oya is the sixth-longest river of Sri Lanka. The 142 km (88 mi) long river runs across four provinces and five districts.