Abstract: Artillery auto-correction technique is important for realizing the automation and intellectualization of tank cannon artillery correction process as well as enhancing the accuracy of firing. A device for photoelectric auto-correction of artillery based on position sensitive detector (PSD) was introduced. By adopting PSD as the photoelectric detector and utilizing the photoelectric conversion and signal processing technology, this device could gain the real-time barrel bending deformation automatically and give the correction of the howitzer, so as to realize the error correction and the automatic correction in the artillery. At different initial positions and shooting angles, the device could achieve the correction precision of 0.1 mil (mil :unit of angle for artillery measuring distance, 1 mil=0.060.001 rad)