Abstract: The ultrasonic shear wave 3D imaging technology has been applied well in concrete structure detection, but the research on this technology is still not deep. In this paper, experiments of different shear wave velocity, transmitting frequency and testing direction were carried out to study the influence of the above factors on the detection results. The results showed that when the deviation of the structural model speed was the same, the deviation of the measured thickness caused by the set value was larger than the actual speed. When the set speed was 30% lower than the actual speed, the internal resolution of the structure also decreased. The shear wave velocity can be obtained by converting P-wave velocity with Gan formula. For detection targets of the same structure at different depths, multi frequency testing will be good. When the test direction was orthogonal to the internal structure, the focusing imaging effect was the best. The oblique survey direction should be avoided, which may cause difficulties in data interpretation.