In order to improve the dispersity of graphene oxide （GO） in asphalt matrix and the performance of GO-modified asphalt， polyether amine grafted GO （PEA-GO） was synthesized， and the chemical structure of PEA-GO was characterized by Fourier transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）， which verified the successful synthetization of PEA-GO. The properties of GO and PEA-GO- modified asphalt with different dosages were analyzed. The results indicate that PEA-GO shows a more obvious improvement effect on the conventional performance of asphalt than GO. At the same dosage， the penetration， ductility， and softening point of PEA-GO-modified asphalt are higher than those of GO-modified asphalt， while the viscosity of PEA-GO-modified asphalt is lower than that of GO-modified asphalt. At the same dosage， G* and G*/sinδ of PEA-GO-modified asphalt are higher than those of GO-modified asphalt. When the dosage of PEA-GO is 0.05wt.%， G* of modified asphalt is the highest， and δ of PEA-GO-modified asphalt is lower than that of GO-modified asphalt. The results show that PEA-GO is superior to GO in improving the high-temperature deformation resistance， elastic recovery ability， and anti-rutting ability of asphalt.