Abstract: In order to solve the problem of the increasingly high requirement of asphalt pavement performance, a solution of reactive elastomeric terpolymer (RET) compounding styrene-butadiene rubber (SBR) was proposed to obtain modified asphalt with superior comprehensive and cost-effective performance. In this paper, the rheological properties and micro modification mechanism of different content of RET compound SBR modified asphalt binders were studied through MSCR test, BBR test, atomic force microscope and Fourier infrared spectrum experiment. The test results show that RET, SBR and base asphalt have interactive chemical reactions and form a new macromolecule material and chemical interactive network structure in compound modified asphalt, which significantly improves high temperature stability, crack resistance at low temperature and storage stability of the compound modified asphalt binders, as well delays the early diseases of asphalt pavement effectively.