Abstract:   The anomaly of elevation has always been a concern in surveying and mapping field, and the commonly used fitting methods are based on least square method. In this paper, the method of moving least square method is used to make the elevation anomaly fitting, and the fitting accuracy is improved by the Engineering data. At the same time, the "fixed point method" is proposed for the determination of the radius in the least square method of moving, and the method can satisfy the fitting precision requirement.