Abstract: In order to enhance the low temperature anti-crack property of asphalt mixture,the paper adopts silica modified material to study the low temperature anti-crack property for asphalt mixture.By indoor tests, it is proved that the physical property of penetration and softening point are improved,and the mechanical property of compressing strain energy and bending strain energy are enhanced.The result shows that silica evidently improves low temperature anti-crack property of asphalt mixture.