The invention discloses an asphalt modification method. The asphalt modification method comprises the following steps: washing, deoiling and drying collected lobster shell wastes; grinding the dried lobster shell wastes to obtain a lobster shell powder having a particle size of 0.15 mm or below; and heating and thawing matrix asphalt, then adding 5-20 wt% of the lobster shell powder, performing manual stirring, and stirring and shearing the obtained mixture in a high-speed shearer to obtain lobster shell powder modified asphalt. The addition of the waste lobster shell powder can increase the rigidity of an asphalt binder and improve the high temperature stability and the creep resistance of the matrix asphalt. Test results can provide a reference for the engineering application of the waste lobster shell powder modified asphalt material, and make the waste lobster shell powder modified asphalt material become a clean and green product.