Abstract: In the integrated navigation system of GPS/SINS,the heading's observability is very weak,although the heading error is improved after Kalman filter,the trend of heading is divergent and is even larger when the SINS of low cost and low precision is introduced.In order to eliminate this divergent trend,the method that AHRS revises the heading of SINS on-line is put forward.The practical static and dynamic experiments illustrate that this method can effectively eliminate the divergent trend of heading,the positioning precision is very high,which provides theoretic basis for the abroad application of GPS/SINS system.