Based on the analysis of the influence of the charge coupled device (CCD) saturation on the image quality of ptychographical iterative engine (PIE), an improved reconstruction algorithm is proposed to get accurate reconstruction from partially saturated data. Compared with the common algorithm, the suggested method can remarkably reduce the data acquisition time without degrading the spatial resolution of the reconstruction, so the requirement on the stability of the experimental setup and the specimen is obviously reduced, and this method is quite meaningful for a wide range of applications of PIE.