Abstract: The acoustic signal characteristrc of ultrasonic brazed interface for the aluminum matrix composites was analyzed according to the structure of brazed joint.The quality assessment of brazed joint of aluminum matrix composites was performed by the advanced ultrasonic imaging technology.The defects and their locations can be predicted by the characteristics of obtained A-scan signal,B-scan and C-scan images,and the ultrasonic results are verified by metallographic analysis of brazed joint.It is found that the ultrasonic imaging technology is an effective way to evaluate the quality of the ultrasonic brazed joint of aluminum matrix composites and detect the defects such as blow hole,oxide film inclusion and incomplete penetration in brazing interface.