Abstract: The discrimination of the attitude change of space targets is of great significance for precise control of hostile targets during space attack and defense operations. In this paper, the method of determine the attitude change of space targets based on inverse synthetic aperture radar (ISAR) image is studied, which is to discriminate whether the attitude state of space targets are steady or changing. Firstly, the basic principle of target attitude change based on ISAR image is derived. Then, the ISAR image rotation angle discrimination method is proposed based on image processing and matching technology. Finally, the effectiveness of the proposed method is verified by radar measured data.