The invention discloses a preparing method of rubber toughening styrene transparent pitch compound, which is characterized by the following: forming rubber particle discontinuous phase with 50-90 wt copolymer continuous phase and 50-10 wt rubber-like polymer; mixing; getting the product; setting the rubber particle discontinuous phase as 20-80 wt core layer copolymer and 80-20 wt shell layer copolymer; proceeding suspension polymerization with 30-60 wt styrene monomer, 20-60 wt (metyl group) acrylic ester monomer, 5-30 wt acrylic nitrile or methacrylonitrile monomer; getting the copolymer continuous phase. This pitch possesses better transparency, shockproof property and chemical medicine resistance property.