A new type of high viscosity modified asphalt was developed by blending and composite modification technology.By optimizing raw materials such as base asphalt,styrene-butadiene-styrene block copolymer(SBS) copolymer,C₉ petroleum resin(PR) and solvent,the composition material and dosage scheme of SBS/C₉PR were determined.Combined with physical properties,fluorescence microscopy,multi-stress creep recovery (MSCR) and dynamic shear rheology (DSR) tests,the physical properties,phase structure,high temperature rheological properties and storage stability of SBS/C₉PR were compared with those of Japanese TPS and domestic SINOTPS high-viscosity asphalt.The results shown that the recommended SBS/C9PR compositions and dosage schemes were SK70 base asphalt,SBS modifier (LG501∶LG411=1∶1),C9PR＿3,solubilizer (furfural extract oil) and crosslinking agent (sulfur) with 4%,5%,2% and 1‰,respectively.The phase distribution of SBS/C9PR was more uniform,and the compatibility between SBS and asphalt was increased by C₉PR and solvent addition,thus showing better storage stability.SBS/C₉PR had good rheological properties at high temperature.It was classified as PG64E at high temperature.It was suitable for extremely heavy traffic asphalt pavement whose pavement temperature did not exceed 64℃.