At the 2008 Summer Olympics in Beijing, Kangni competed again for the second time in the 400 metres. She ran in the seventh and final heat against six other athletes, including Jamaica's Shericka Williams, who eventually won the silver medal in the final. She finished the race in seventh place by five seconds ahead of Swaziland's Temalangeni Dlamini, outside her personal best of 54.16. Kangni, however, failed to advance into the semi-finals, as she placed forty-fifth overall, and was ranked farther below three mandatory slots for the next round. Following her elimination from the heats, Kangni announced that the Olympic games in Beijing was a "great feast for the sport", and also, represented the culmination of her career.