Dynamic moduli of stabilized rubber modified asphalt(SRMA) mixtures with twelve kinds of gradation composition in eight mixture types were tested, and dynamic mechanical characteristics of SRMA mixtures were analyzed based on the test results. In order to improve the prediction accuracy of Witczak model on dynamic moduli of SRMA mixtures, Levenberg Marquardt nonlinear regression method was used for the model revision. The results show that SRMA mixtures have good dynamic mechanical properties, and dynamic moduli of SRMA mixtures can be preferably predicted by the revised Witczak model.