Abstract: In this paper, for the characteristics of the Y tubular joint, we specially designed the inspection craft of Y tubular joint using ultrasonic phased array and computer-aided technology in order to solve these problems of defect positioning difficulty, complexity of the method, serious time-consuming in the ultrasonic inspection. The results of the study show that it is beneficial to improve the detection efficiency of Y tubular joint with ultrasonic phased array inspection technology and to reduce the movement of the probe in conventional way with ultrasonic phased array inspection technology.