The team claimed the highly contested match with sets of 25-15, 21-25, 23-25, 25-11, 15-9, in an encounter that lasted for two hours and 16 minutes at the Kigali Arena.
Rwanda goes into the quarterfinals as the leaders of Group A. Uganda will advance as runners up.
During the match, Rwanda was led by outside hitter Yves Mutabazi, as the 27-year-old grabbed 23 points, while seasoned player Yakan Guma got 14 and Patrick Kavalo added 12.
Gasango and Flavien Ndamukunda led on on the blocking end with three blocks while Placide Madison Sibomana and setter Ivan Mahoro had two.
Yves Mutabazi starred after shooting two ace-services and Vincent ‘Gasongo’ Dusabimana and Flavien Ndamukunda had one each.
Uganda’s Dawidi Okello led the scoring with 28 points.
In other matches, Ethiopia lost to Nigeria (20-25, 12-25, 34-32 and 17-25), South Sudan was thrashed by Tunisia in Pool D 0-3 (11-25, 14-25 and 12-25).
Kenya best Tanzania with a forfeit match of 3-0 (25-0, 25-0 and 25-0) after failure to pay registration fees.