在CCD星敏感器中,星点图像质心定位的准确性影响星图识别的正确性,也决定了星敏感器测量的有效性。质心法是星点质心亚像元定位的传统方法,然而,它存在系统误差和随机误差。分析了误差产生的原因。在传统质心法的基础上提出了采用二元线性插值和自适应质心窗来改善信噪比,并对误差进行校正,实验证明了它比传统的质心法有更高的精度。 In the CCD star sensor, the accuracy of the positioning of the centroid image centroid affects the correctness of the star image recognition and also determines the effectiveness of the star sensor measurement. The centroid method is a traditional method of positioning the centroid and centroid sub-pixel. However, it has systematic errors and random errors. The reason of the error is analyzed. Based on the traditional centroid method, the binary linear interpolation and adaptive centroid window are proposed to improve the signal-noise ratio and to correct the error. Experiments show that it has higher accuracy than the traditional centroid method.