Abstract: In order to study the mechanical properties of the ultra-high performance concrete (UHPC)-thin polymer overlay (TPO) ultra-thin paving system under different vehicle axle load, horizontal force, thickness of TPO and load positions, the orthogonal experiment designs and the finite element calculations were carried out. The results show that with the increase of axle load, maximum tensile stress of UHPC, the maximum tensile stress of TPO and shear stress between UHPC and TPO increase significantly. The effect of horizontal force on the maximum shear stress between UHPC and TPO is significant. Increasing the thickness of TPO is beneficial to reducing structure stress . Considering the adverse conditions of the overload of 230% and emergency braking, maximum tensile force of UHPC and TPO are both less than their respective cracking strength, the maximum shear stress of UHPC-TPO is much smaller than that of the shear strength of interface.