Abstract: A method of change detection using aerial images with POS data is presented.Firstly,the new images' orientation parameters are resolved using the old aerial images with POS data in the same area,and feature points are extracted in old images,and new images' conjugate points are computed using forward intersection and collinearity equations.Then gray matching are done with the conjugate points,and the points which can not match well are found.These points will be preliminary regarded as been changed,and based on them,check-up windows are selected for the next precise detection.Edge extraction and chain code trace are done in these windows,and the corresponding chain codes are matched.At last the change areas are obtained according to the matching results.Experiment proves that this method is feasible,and gets relatively encourage result.