The invention discloses a novel shell calcium oxide produced by microwave. The raw materials of the shell calcium oxide are one or more of an oyster shell, a scallo, a pearly shell or a fan shell. The production method comprises the following steps: adding sand and water into the shell raw material in arbitrary proportion, mixing and performing abrasive cleaning, drying and smashing till the grain diameter of 0.5-3cm; and performing microwave drying through three stages, wherein the microwave intensities are in turn 100 kilowatt, 200 kilowatt and 250 kilowatt, the microwave temperatures are in turn 600 DEG C, 1200 DEG C and 1400 DEG C, and the baking times are in turn 1h, 3h and 2h; performing high micro-grinding on the dried materials till the grain diameter is 4-30 um to obtain the product. The novel microwave produced shell calcium oxide is simple in manufacture process, environmentally friendly and energy-saving, short in burning time, high in production efficiency, high in product purity and good in quality, avoids the contact with the other fuels such as coal, reduces the residues of the heavy metal and the sulfide in the product, is widely used for food adding and subsidiary agricultural product washing, and can effectively remove the pesticide residue on the surface of the subsidiary agricultural product.