Abstract: In order to improve spatial resolution of reconstructed image, grid-shaped collimator usually was preinstalled on detector in high energy X-ray industrial CT system. However, the scanning data acquired under such circumstances was sparse. To solve this problem, multiple round-multiple scanning method was provided, but it greatly reduced the efficiency of data acquisition. Then, a single round-multiple scanning method and the corresponding iteration algorithm which was capable of taking into account scanning efficiency and reconstruction image quality was proposed. Numerical experimental results verified the effectiveness of this method.