Abstract: Because dithering and vibrating exist inevitably while complex satellite running, this will lead to nonsteady and lower precision for star-sensor measurement data and difficult in data processing at low SNR. Therefore, in this paper, the data processing method in the condition of complex satellite dithering is discussed. Firstly, the measure principle and error mechanism of star sensor in satellite attitude determination are analyzed, and then on the basis of these analysis, the attitude measurement data processing technique in condition of satellite dithering is researched detailedly. Combined with the amplitude and frequency character of dithering signal, the influence of dithering to the measurement precision of star sensor is analyzed by using of searching the boundary point of amplitude and frequency for treating dithering error. In addition, integrating with the process of satellite attitude determination, the measurement data processing method of star sensor in the dithering condition is presented, which can effectively enhance the data precision for star sensor observation and make it possible to utilize dithering measurement data without steady state control. The method has the advantages of decreasing design cost and shortening design period.