Abstract: During the automated ultrasonic inspection of weld seam of high frequency welding(HFW) pipes, it is very difficult to track the weld seam accurately, which will affect the reliability of inspection easily. Through the analysis of ultrasonic inspection techniques, and inspecting with 6 dB sound beam full wall thickness overlap area, a new set of ultrasonic inspection technology was put forward. Practice showed that, in the event of inexact seam track, the technology can assure the reliable inspection result, and provided a effective method for the automated ultrasonic inspection of weld seams of HFW pipes.