A method for verifying scan precision of a laser measurement machine includes the steps of: preparing a transparent flat, of which the flatness of each plane is regarded as a flatness conventional true value; determining an optimum scanning mode; determining optimum scanning parameters under the optimum scanning mode; scanning the transparent flat under the optimum scanning mode and the optimum scanning parameters for certain times, and obtaining measuring data; calculating a plurality of flatness values using the measuring data; calculating an average value and a standard deviation of the flatness values, and a bias between the average value and the flatness conventional true value; evaluating the repetitiveness of the laser measurement machine according to the standard deviation; and evaluating the veracity of the laser measurement machine according to the bias.