Just as fellow-American Paul Hamm did Wednesday evening in the men's event, Patterson rallied with two sensational performances to close out the competition.
Hamm was 12th midway through Wednesday night's event before making a shocking comeback to become the first American male Olympic all-around champion.
Patterson did not have to come from as far behind as did Hamm, but she still trailed after two rotations following a less-than-stellar effort on the vault -- the same exercise that almost cost Hamm.
But Patterson then turned in the best performance of the evening on both the balance beam and floor exercise to score 38.387 points.
Svetlana Khorkina of Russia was second with 38.211 and Zhang Nan of China was third at 38.049.
Patterson is the first American medalist in the women's all-around since Shannon Miller won a silver in 1992. The only other American gold in the event came from Mary Lou Retton in the boycotted Games of 1984.