Abstract: The Simultaneous Imaging Polarimetry (SIP)is a new type of remote sensing detection technology. The imaging polarimetry architecture refered in the paper is Division of Amplitude, which can simultaneously obtain four polarization intensity images (in the orientation angle of 0,45,90 and 135 degree)of the same target on the same detector. Affected by self -polarization, error of polarization element and coating of the system, the orientation angle of polarization will be deviated. In order to ensure the polarization measurement accuracy, the orientation angle of polarization was calibrated using two methods (Equator-Poles calibration and curve fitting). Results show that the difference between these two methods is less than 0.4%, and degree of linear polarization (DOLP) accuracy of measurement and principle calculation is all within 2%, which prove the effect of the calibration.