A method for calibration transform matrix between sun sensor and cubic prism coordinate system was proposed. First

sun sensor and 2D rotator coordinate system was calibrated with sun simulator and high-accuracy 2D rotator. Second

cubic prism and 2D rotator coordinate system was calibrated with diaphragm screen and CCD image-collimate system. Finally

the transform matrix between sun sensor and cubic prism coordinate system was derived with 2D rotator as medial coordinate system. Thereby

Sun vector measured by sun sensor was indirectly transferred to cubic prism coordinate system. Experiment show that the calibration precision was better than 4(1σ) and meet the requirement of sun sensor measurement. The method need not precise machining and installation

and make it unnecessary that sun sensor and 2D rotator coordinate system should be the same when calibration. The method was easy to carry out and valuable for application.