Abstract: A new nondestructive testing and evaluation (NDT&E) technique by using multiple-view ultrasonic imaging based on mobile automated scanning system for pipe welds in-service was described. Ultrasonic C-scan and three-dimensional P-scan were established to evaluation and diagnosis of defects in pipe welds. The results presented showed that the characteristics of defect in weld, for examples, location, distribution and orientation and size of defects and so on, were be exhibited well by employing the approach. It offered an effective instrument for improving NDT&E detectable probability and reliability of finding defects. The developed multiple-view ultrasonic imaging technique had been applicated in NDT&E of pipe welds in steam power industry so far.