Abstract: Aiming to address low reconstruction accuracy caused by improper selection of matching source in the stereo matching process of left and right images in binocular structured light 3D reconstruction, a matching method based on absolute phase is proposed to reduce the mismatch rate and improve the reconstruction accuracy. Firstly, based on the absolute phase solved by phase shift method and multi-frequency heterodyne method, the polar line constraint is used to create a search matching area by global search and local search for the pixels of the left and right images. Then, cubic spline interpolation is performed on the search area to achieve sub-pixel stereo matching. Finally, the triangulation principle is used to complete the conversion of the two-dimensional coordinates of the matching points to three-dimensional coordinates, and the three-dimensional reconstruction of the target surface is realized. The experimental results show that the method proposed reduces the matching time by 87.77% compared to SAD and SSD matching algorithms, and improves the reconstruction accuracy by 77.75% and 90%, respectively, demonstrating its strong generality and practicality. Particularly, the point cloud reconstructed in 3D has no water ripple phenomenon, and the surface is smoother and closer to the actual object.