Abstract: The steel bridge deck pavement materials are susceptible to damage caused by temperature, among which tensile damage is the most common. Modified polyurethane concrete is a new type of steel bridge deck pavement material. In order to study the effect of temperature on its tensile properties, uniaxial tensile experiments were carried out at −10°C, 0°C, 15°C, 40°C and 60°C. In order to ensure the success of the experiment, two kinds of experimental specimens (dumbbell-shaped specimen and dumbbell-shaped specimen with circular arc edge) were first designed. Meanwhile, a novel tensile testing fixture used to match the specimen was designed, and the experiment comparison of the two specimens was carried out. Through the uniaxial tensile experiment, the stress-strain curves were obtained and the tensile performance indexes were calculated according to the curve. The results show that using the dumbbell-shaped specimen with circular arc edge and the new tensile testing fixture has better effect. The new fixture can restrain the deformation of the fixture by adding bolts, so as to effectively reduce the stress concentration in the loading process. With the increase of temperature, the tensile strength and tensile elastic modulus of modified polyurethane concrete decrease. The peak strain, fracture energy density and tension-compression ratio all increase. The temperature related expressions of the tensile performance indexes are proposed. The uniaxial tensile constitutive relation of modified polyurethane concrete is constructed, and the calculation is in good agreement with the experimental results. The results can serve as basic references for the future engineering application of this material.