Based on the azimuth,elevation angle and ranging characteristics output by the Landing Guidance System,as well as the working principle and output characteristics of the INS, the dynamic error estimation of the INS position information is carried out using the Landing Guidance Information. In the case of short-term interruption of the Landing Guidance information or data corruption, the error parameters are utilized to correct the INS information and supplement and enhance the Landing Guidance Information, thereby achieving continuous and available landing guidance capability of the Landing Guidance System.