To provide a microwave dryer capable of drying a drying object placed on a plurality of plates as uniformly as possible.

In the microwave dryer provided with microwave transmitters 18, 18... irradiating microwaves on a drying object placed in a drying tank 10 decompressed by a vacuum pump 12 and heated by a heater 14 or the like to dewater it, a plurality of microwave transmitters 18, 18... are installed at both sides of a laminated body 22 in which a plurality of plates 24, 24... mounting the drying object are stacked in layers at every vertical specified distance, inserted in the drying tank 10 so as to irradiate microwave from both sides and a reciprocally driving device 40 reciprocating plates so as to vertically move with regard to the irradiation direction of microwaves from the microwave transmitters 18 is installed for each plate 24.