Aiming at the existence of a large number of dangerous and complex underground culverts in the city, which make it inappropriate or impossible for human beings to enter, it is of great significance to develop mobile robots with multi-terrain adaptive characteristics to realize the tasks of material handling and equipment inspection in the culverts. 2-PRU/UPR parallel mechanism was proposed. The 3D model of the 2-PRU/UPR mechanism was constructed by SolidWorks software. The degree-of-freedom characteristics of the 2-PRU/UPR mechanism were solved based on the constraint force coupling analysis of helix theory, and the theoretical validation was completed by the joint modified G-K formula. The kinematic inverse of the mechanism was solved by the closed-vector chain-of-motion equations, and the 3D point cloud map was generated by the point cloud algorithm in MATLAB to generate the workspace of the mechanism. The 3D point cloud map was generated by the Adams software, and the 3D point cloud map was generated by the Adams software. The virtual prototype simulation was carried out in Adams software. The results show that the 2-PRU/UPR mechanism has three degrees of freedom, including translational degrees of freedom along the Z-axis and rotational degrees of freedom around the X-axis and Y-axis, and its workspace has a centrosymmetric distribution and a wide range of coverage, with a good smoothness of motion. 2-PRU/UPR mechanism has a simple structure, is fast, and has a large workspace, which can be used instead of manual labor to complete the handling of underground culverts, inspection and other work, and greatly improves the work efficiency.