Abstract: The sensor support structure is the core and key to the structural design of piezoelectric ultrasonic pipeline corrosion detector, and its stability in the process of detection determines the accuracy of detection data. To meet the urgent demand of long-distance pipelines for the piezoelectric ultrasonic based pipeline corrosion in-line inspection technology, a design scheme of piezoelectric ultrasonic sensor support structure suitable for the corrosion in-line inspection of in-service pipelines was proposed in this paper, and the three-dimensional virtual prototype was also designed. Then, kinematics simulation analysis was conducted. It is shown that this support structure can fit the pipe wall in every situation. Finally, its structural stability and its design scheme's feasibility were verified further by testing this senor support structure on the rotary test platform. The design scheme is of great significance to the localization of piezoelectric ultrasonic pipeline corrosion detection technology and equipment.