The invention discloses a picture correction method and system based on an ORB algorithm. The ORB algorithm and perspective transformation are combined in use. The method comprises the specific operation steps of S1, feature point detection; S2, feature point description; S3, feature point matching; S4, preliminary screening of matching point pairs; S5, acquisition of first N optimal point pairs;S6, calculation of a homographic matrix H; and S7, image registration and correction. Compared with existing methods, the method has the remarkable advantages that operation speed is 100 times that ofa SIFT algorithm and 10 times that of a SURF algorithm, correction precision is higher than that of the SIFT algorithm and slightly lower than that of the SURF algorithm, the method has rotation invariance, and the noise sensitivity problem is solved, so that the final correction effect is certainly ideal; and during calculation of the homographic matrix H, a random sampling consensus (RANSAC) algorithm is adopted, so that the homographic matrix H is solved more robustly, and mistaken matching points are eliminated.