In the system of real-time orbit determination of synchronous satellite, an algorithm based on simple features fusion is proposed to reduce the consuming time on star extraction from star image of CCD drift-scan. Firstly, segment star targets and background to decrease the influence of noise and improve the contrast of star image. Then, compute part maximum pixel gray value and mean contrast of partial region as star target feature and fuse the features, by counting optimum weights, to make the star target be sharper. The precision of star extraction is higher than traditional star extraction method. The amount of calculation of the algorithm which can be easily fulfilled is small, star extraction time is saved and the accuracy of star extraction is improved. The experiment results of processing the star image whose resolution is 1 528×1 528 taken by drift-scan CCD proves the validity of the algorithm.