To provide a high precision blast working method to efficiently carry out fine working of a hard and fragile material such as silicon, ceramics, and glass in high precision.

Used abrasive grains are recovered after blast working is carried out by injecting original abrasive grains a grain diameter of which is within a specified range, fine powder crushed and produced by wear and tear is removed from the recovered used abrasive grains, additional abrasive grains having a grain diameter larger than the original abrasive grains are added to the recovered abrasive grains from which the fine powder is removed and are mixed, and blast working is carried out by the mixed abrasive grains grinding efficiency of which is recovered in the same level as grinding efficiency at the initial stage of injection of the original abrasive grains.