Abstract: Nondestructive testing of double-sided superimposed shear wall structures was carried out by array ultrasonic imaging technology. It was found that there existed large errors between the depth of targeted object and the actual depth. The causes of the error were analyzed by theory and finite element simulation. The results showed that the error was caused by the difference between the strength of the postcast concrete and that of the precast concrete on both sides, and the ray tracking technology can be used to improve the detection results. The double-layer concrete test blocks with different strengths were poured, and array ultrasonic imaging was carried out to further confirm the detection errors and causes. It was found that the detection errors were more than 10%. Ray-tracking technology was used to improve imaging results, with an error of less than 3%. The above results had guiding significance for array ultrasonic imaging detection in double-sided superimposed shear walls.