A three-lens polarizing CCD camera is presented in brief. After the response nonuniformity of the detector used in the three-lens polarizing CCD camera and its response nonuniformity in three polarization directions are analyzed, a correction method based on radiation calibration is proposed. The real polarization of the polarized light, the polarization of the original polarized image and the polarization of the image corrected by using the nonuniformity correction method are calculated respectively in the polarization measurement experiment. The result shows that this nonuniformity correction method can improve the analytic precision of the polarization information in an image.