PURPOSE: To provide a method of controlling and eliminating the extent of oil and fat content stuck to a blasting member of shot or grit, etc., simply up to less than the specified value and a shot blasting unit therefor.

CONSTITUTION: After sampling a blasting member projected to a product, the extent of oil and fat content stuck to the sampled blasting member is measured by an oil-fat content measuring device 6, and the measured oil-fat content is compared with the, preset oil-fat content by an arithmetic unit 7, and when the measured value is higher than the preset one, an oil-fat content absorbe powder is charged into a circulating system by a feeder 9, and then the oil-fat content absorbent peer unstuck to the blasting member after being charged is recovered for reuse. In addition, the blasting member stuck with the absorbent powder is projected into a cabinet 1, the oil-fat content stuck powder separated from the blasting member by the projection is recovered by a recoverer 5.