To provide a blast washing method capable of adjusting washing ability by changing hardness, a shape and a size of the solid carbon dioxide used as a shot material, a manufacturing method for solid carbon dioxide used for it and a manufacturing device.

The blast washing method includes a step of producing the plate-like solid carbon dioxide for using crushed pieces for the shot material (step S10); a step of transporting the produced plate-like solid carbon dioxide to a working field (step S20); a step of crushing the plate-like solid carbon dioxide at the working field or the like (step S30); a step of throwing the crushed pieces to a washing device (blast device) (step S40); and a step of spraying them to the article to be washed (step S50) to perform washing.