Abstract: The theoretical basis of magnetostrictive ultrasonic guided wave inspection was introduced.The transmission characteristics of guided wave in long range pipeline were obtained by building up modal analysis of the pipeline.Experimental tests were carried out for laboratory pipeline and field pipeline,respectively,and results showed that inspection by using the magnetostrictive ultrasonic guided wave could greatly enhance the testing efficiency for the long range pipelines and it could reach the sensitivity of detecting variation in cross section change of less than 1%.Current method of magnetostrictive ultrasonic guided wave inspection could provide strong support for the safe running of the pipelines.