To reduce the construction temperature of asphalt pavement，reduce energy consumption and environmental pollution，warm mix asphalt mixture technology is introduced. At home and abroad，the exploratory research on reducing the construction temperature of asphalt pavement by adding viscosity reducer has been carried out.If it was not used properly，it would seriously affect the road performance of asphalt pavement. In this pstudy，two kinds of viscosity reducer EC120 and Sasobit were selected to carry out research. Through viscosity test，it was determined that the optimum content of EC120 in 70^# A road asphalt is 3.5%，and the optimum content of EC120 and Sasobit in SBS modified asphalt is 3%；The road performance tests of AC-13C and SMA-13 mixtures were carried out at the optimum dosage of EC120 and Sasobit. The results showed that the high temperature rutting resistance，water damage resistance and fatigue performance of the two mixtures are significantly improved，and the low temperature cracking resistance of SMA-13 mixture is slightly reduced. However，it can meet the technical index requirements of modified asphalt mixture.