The mechanical properties of polyurethanesteel sandwich structure orthotropic bridge deck at different section control points were analyzed under different vehicle loading statuses. These properties with the core layer thickness and faceplate thickness were obtained by means of the 3D finite element models of a threespan sandwich orthotropic bridge deck. The results have shown that the mechanical characteristics of the sandwich bridge deck are as follows: on the top of the middle longitudinal U stiffening rib at the midspan section, the compressive and tensile properties of the longitudinal and transversal stress of the sandwich deck subface are not the same as the usual flexural member, the longitudinal stress on U stiffening rib subface is much bigger than that in any other location of this section, its transversal stress can be negligible, and that the longitudinal stress of polyurethane core layer is the maximum at the joint of the middle stiffening rib connecting the sandwich bridge deck in supporting section, its transversal stress can be negligible, and the shear strength of the faying surface between the steel plate and the polyurethane is higher than 6Mpa, which can meet bonding strength requirements.