The world number one had stormed through the opening rounds, and stopped her semi-final early with a convincing 19-7 victory over Lucija Zaninovic of Croatia.
Yague Enrique, a three-time world champion herself, had come from behind in her semi-final with an amazing late rally against Chanatip Sonkham.
The 31-year-old - who missed the Beijing 2008 Games through injury - soon trailed again, as Wu opened up a 4-0 first-round lead.
This time, there was no way back as the 25-year-old Chinese fighter closed out what was in the end a comfortable 8-1 victory.
Thailand's Sonkham, who had beaten number two seed Shu Chun-Yang of Chinese Taipei in the quarter-final, claimed bronze with victory over repechage winner Elizabeth Zamora Gordillo of Guatemala, who had lost to Wu in the first round.
Zaninovic - whose twin sister Ana fights at -57kg tomorrow - picked herself up to win the other bronze when she beat Mexican Jannet Alegria Pena on golden score.