The bonding strength of ordinary emulsified asphalt is insufficient to meet the requirements of preventive maintenance or cold mixing and cold paving. SBS modified emulsified asphalt ( SBS-Emu ) was prepared by modifying first and then emulsifying. The effects of SBS modifier, activated cross-linker, emulsifier and stabilizer content on SBS-Emu storage stability, particle size distribution and road performance based on emulsified asphalt performance graded (EPG) system were investigated. The results show that the storage stability of SBS-Emu deteriorates with the increase of SBS content and becomes better with the increase of emulsion stabilizer and emulsifiers content. Activated cross-linkers can improve the storage stability of emulsified asphalt within certain limits. The high-temperature performance and low-temperature performance of SBS-Emu increases with the increase of SBS content. Crosslinking stabilizers can improve the high-temperature performance and low-temperature performance of SBS-Emu in a certain concentration range. The high temperature performance is the best when the content is 1.5%, and the low temperature performance is the best when the content is 1.0%. The low temperature performance of SBS-Emu is improved with increasing emulsifier content, and the excessive content is unfavorable to the high temperature performance. Emulsion stabilizer has little effect on the high temperature performance and low temperature performance of SBS-Emu.