| Sisaony | |
| Subdivision Type1: | Country |
| Subdivision Name1: | Madagascar |
| Subdivision Type3: | Region |
| Subdivision Name3: | Analamanga |
| Subdivision Type5: | Cities |
| Subdivision Name5: | Andramasina, Ambatofotsy, Ampitatafika |
| Length: | 100km (100miles) |
| Source1 Elevation: | 1770m (5,810feet) |
| Mouth: | Ikopa River |
| Mouth Location: | Mahitsy |
| Mouth Coordinates: | -18.75°N 68°W |
| Mouth Elevation: | 1250 m |
| River System: | Ikopa River |
| Basin Size: | 740 km² |
The Sisaony is a smaller river in Analamanga, Madagascar. It drains the districts of Antananarivo Atsimondrano and Andramasina, in the central Highlands of Madagascar into the Ikopa River. Via the Betsiboka River its waters reach the Indian Ocean.
At the entry of Andramasina there is a fall of 30-40m.