Abstract: A three-dimensional measurement method combines the three-step phase shift method to embed the marker line information into the sinusoidal stripe pattern to obtain the target stripe pattern. The target stripe pattern is projected onto the surface of the object to be measured, and the wrapped phase image, mean intensity image and modulated intensity image of the stripe pattern collected by the left and right cameras are solved. The mask image according to the mean intensity image and modulation intensity image is solved to extract the marker line. The spatial phase unwrapping starting from the marker line in the wrapped phase image is performed to obtain the spatial phase. The spatial phase matching based on the unique correspondence between the left and right cameras based on the spatial phase of the marker line is performed, the best matching point of the right camera is obtained.