With the development trend of precision-guided weapons to light-duty, miniaturization, low cost and high flexibility, strapdown optical image seeker arises. It removes the complex and expensive gimbal structure, so its volume weight and cost reduce dramatically, and the reliability is improved significantly. In this paper, in-depth study was performed on the strapdown optical image guidance system, and the working principles of the gudience system and the seeker were analyzed in detail. It laid the theoretical basis for the development of the strapdown optical image seeker and the research of its guidance technology, showing important military significance.