Abstract: Sun sensor is the key component of the attitude measure on the satellite.Its principle is to determine the satellite direction by measuring the elevation and azimuth angle between the sun sensor and sunlight.With the development of the MEMS and high resolution image sensor technology,the accuracy of the new sun sensor is improved magnitude by combining the MEMS sunlight lead-in and APS CMOS image sensor,the combination which without additional volume and power consumption decrease the random error of this sensor system by the multi-image matrix.Meanwhile,with the Future Extraction and Image Correlation algorithm,the system robustness is improved.Even when some blockades happened at some sunlight holes,the system can work well with almost no loss of the accuracy by the algorithm.The accuracy of the traditional sun sensor,which is consist of only one single hole light lead-in and CCD etc.,is relatively unreliable.With this new construction and implementation method in the design of the system,the reliability for the new solar sensor is guaranteed.