Joyce Ekworomadu paced Nigeria with a team-high 15 points as they kept their Olympic hopes alive with a 65-55 victory.
Sonia Guadalupe hit three-pointers to lead Angola with 13 points but they finished out of the podium for the first time since 2005.
With the victory, Nigeria clinched the last spot available for the Women's Olympic Qualifying Tournament to be played next year.
Nadir Manuel, Angola's leading scorer and rebounder, fouled out with 4:00 minutes remaining, and the Nigerian front-court dominated the Angolan painted area.
Stats Don't Lie: Even though Angola shared the ball a lot better than they did in the previous seven games, Nigeria's suffocating defence in the final quarter disrupted Jaime Covilha's side. Manuel scored only two points in the third quarter before fouling out.
Game Hero: Ekworomadu scored six crucial points, including a three-pointer, in the third quarter to keep Nigeria in the contest.
The Bottom Line: After losing to Angola in the Group Phase, Nigeria showed a lot more determination to win the contest. Following a heartbreaking 71-70 Semi-Final defeat to hosts Cameroon, Scott Nnaji team's stepped on floor to do whatever was necessary to keep their Olympic dreams alive.