The invention provides a double ash lime screening method. The screening method is simple to operate and easy to enforce, and all-level aggregates obtained through the screening have obviously reducedwater absorption rate, wear value and crushing value and slightly improved apparent density, and overcome the physical performance defects of too high water absorption rate, wear value and crushing value of double ash lime, so the drying shrinkage cracks of a mixture obtained through applying coarse aggregates to a mixture are reduced, and the compressive strength of the mixture is improved. Theinvention also provides a modified cement. The aggregates with the particle size of (0, 0.075] mm, obtained through the screening method, are used to substitute parts of a cement raw material, so theutilization rate of double ash lime wastes is increased, the use amount of the cement is reduced, and resources are saved; and the use amount of the cement is reduced, so hydration heat generated during the hydration of the cement is reduced.