Abstract: Computer Simulation of X-ray Projections can be used to exclude the random errors during the X-ray tomography scan.It can be used for verifying the correctness of the scan mode and image reconstruction method,and providing theoretical basis for the actual system implementation and improvement and reconstruction algorithm.While most of the simulation focused on cylinder and ellipsoid,we make simulation of cuboid samples in typical CL system in this paper,as printed circuit is approximate sheet-like cuboid.We compared the Experimental and simulation results and get satisfactory results.The work provides a good foundation for improving image reconstruction algorithm,analyze errors and correct artifacts.