To provide a system capable of treating incinerator ashes remaining after incinerating industrial waste at a higher recycling ratio.

The incinerator ash treatment system for industrial waste comprises a crusher for crushing incinerator ashes, a magnetic sorter for separating magnetic substances such as iron from the incinerator ashes crushed by the crusher, and a dry ball mill for further pulverizing the incinerator ashes after separation of the magnetic substances by the magnetic sorter and an inside sieve and an outside sieve are installed while being overlaid in the outlet of the ball mill. The inside sieve has sieving meshes with a shape and a size capable of separating the pulverized product from the pulverization medium and the outside sieve has smaller sieving meshes than the inside sieve with a size proper for discharging the pulverized substances with a prescribed size or smaller and further, the outside sieve is made so detachable as to discharge the pulverized substances which cannot pass through the outside sieve but the inside sieve after the pulverized substances with the prescribed size or smaller are discharged.