Microwave drying is a new type of drying method. When dry, the microwave energy directly acts on the molecules of the medium and converts it into heat energy. Since the microwaves have penetrating properties, the medium is heated at the same time inside and outside without heat conduction, so the heating speed is very fast. The drying speed can be shortened for foods with water content below 30%. Hundreds of times. At the same time, regardless of the shape of any object, since the inside and outside of the medium of the object are heated at the same time, the temperature difference between the inside and outside of the material is small and the heating is even, and no external coke intrinsic condition occurs during the conventional heating, so that the drying quality is greatly improved.