In order to investigate the influence of graphene treated with PVP on the rheological properties of SBS modified asphalt, composite modified asphalt was prepared by adding different amounts of PVP modified graphene to SBS modified asphalt through a high speed shear. The dynamic shear rheometer(DSR) and temperature sweep and linear amplitude sweep(LAS) tests were used to observe the changes of rheological properties and fatigue resistance of graphene/SBS composite modified asphalt with different contents, combined with bending beam rheometer(BBR) to explore the change of the low temperature crack resistance of composite modified asphalt. The results show that addition of graphene can effectively improve the deformation resistance and elastic recovery ability of SBS modified asphalt under high temperature conditions and the fatigue resistance of SBS modified asphalt. However, the addition of graphene has a negative impact on the low temperature crack resistance of the composite modified asphalt, though the impact is not obvious.