Structured light illumination imaging has important applications in three-dimensional(3D) measurement of close-range high-resolution objects. Based on traditional structured light illumination imaging, a dynamic background light interference suppression technology based on invisible structured light three-dimensional imaging is proposed, a 3D contour of an actual target is acquired, and the anti-interference ability of dynamic background light is analyzed and studied in detail. The generation of structured light is based on the principle of laser interference. The emitting side projects two orthogonally polarized beams, and no interference fringes are generated on the surface of the object. The receiver uses synchronous phase shifting technology to achieve the detection and reconstruction of the structured light stripe. Based on the synchronous phase shifting technology, a four-step phase shifting fringe image is obtained simultaneously, the background light interference can be effectively reduced, and the dynamic 3D imaging capability is improved. In this paper, we theoretically analyze the principle of invisible structured light imaging and the mechanism of dynamic background light suppression, establish an experimental verification device, and obtain a 3D reconstructed image of the actual target under dynamic background light interference. The experimental results are in agreement with the theoretical analysis results.