To obtain modified asphalt mixtures with excellent properties, SEBS and crumb rubber (CR) are used for compound modification of the asphalt, and orthogonal test design is adopted to optimize the blending scheme of composite modified asphalt. At the same time, the three major indicators, brookfield viscosity, short-term aging (RTFOT) tests were used to evaluate the viscosity, high temperature stability, low temperature crack resistance, temperature sensitivity and aging resistance of composite modified asphalt, rubber modified asphalt, SEBS modified asphalt and matrix asphalt. Orthogonal test results show that the optimal compounding amounts of SEBS and CR are 5% and 16% respectively, and the best preparation scheme is to add SEBS and CR at the same time. The SEBS/crumb rubber composite modified asphalt prepared by this method can reduce the temperature sensitivity of asphalt, improve the low-temperature crack resistance and aging resistance performance, and the effect of improving the high-temperature stability is particularly obvious. In addition, it is necessary to consider the target demand and the proportion of compound modified asphalt when the temperature difference changes greatly.