The Monasavu Dam is a rock-fill embankment dam on the Nanuku River about 60 kilometres (37 mi) northwest of Suva in Naitasiri Province, Fiji.

To offset fossil fuel imports for power production on the island, the Monasavu-Wailoa Hydroelectric Project was authorized by the Fiji Electricity Authority in 1977 and construction began in May 1978.

The dam, protection of its catchment and rainforest contribute to its national significance as outlined in Fiji's Biodiversity Strategy and Action Plan.

The power station contains four 20 megawatts (27,000 hp) Pelton turbine-generators and the drop in elevation between the reservoir and power station affords a hydraulic head (water drop) of about 625 metres (2,051 ft).

This share dropped to 49% in 2006 due to growing power demand.