Abstract: The advantage of using magnetostrictive guided wave for online inspection of high temperature pipeline is illustrated. Using MsSR3030R guided wave inspection system, the online corrosion inspection of high temperature pipeline was carried out, and the acquisition progress,analysis and test result were stated. The result shows that using magnetostictive ultrasonic guided wave is precise and practical in high temperature online inspection and could fill up the blank in field of online corrosion inspection of high temperature pipeline.