Asphalt mixture is a kind of typical elastic-viscoplastic material. Environment temperature and loading condition will greatly affect its performance. As the temperature falls, asphalt pavement will engender a shrinkage deformation under the action of temperature stress. When the accumulated temperature stress exceeds tensile strength, the asphalt pavement will be cracked. Based on the results of the bending creep test in low temperature, the Burgers model was established and the viscoelastic parameters in the model were given, and the relaxation modulus of asphalt mixture was also determined in this paper. The study indicated that SBR modified asphalt mixtures have the advantage over common asphalt mixture in low-temperature performance.