Abstract: The weight of components on board satellite is uncertain due to inheritance difference in the stage of satellite configuration and layout design. However, the uncertainty conforms to the laws of mathematical statistics and is still controllable. To reduce the risk of overloading caused by the uncertainty in component weight, this paper adopted mathematical statistics at the stage of configuration and layout design for satellite to optimize traditional weight characteristic calculation to weight characteristic control. Based on the mathematical expectation calculation of the weight of single units and subsystems, the upper and lower deviation within a certain confidence interval was obtained. Thus, the allowable weight of the satellite was utilized utmostly within a high probability range, and the deviation range of the satellite centroid in a certain confidence interval was calculated. According to the calculation results, multiple installation positions for a device (or several devices) in the satellite configuration and layout were designed to realize the satellite centroid control accurately. This method has been successfully applied to a satellite and has achieved good engineering effect.