The Melolo River is a river of Sumba, Indonesia.
The river flows along the northern area of Sumba with predominantly tropical savanna climate (designated as As in the Köppen-Geiger climate classification). The annual average temperature in the area is 27 ðC. The warmest month is October, when the average temperature is around 32 ðC, and the coldest is January, at 24 ðC. The average annual rainfall is 966 mm. The wettest month is December, with an average of 206 mm rainfall, and the driest is August, with 4 mm rainfall.