The invention relates to an intermittent microwave vacuum laundry drying device. The device comprises a vacuum drying sealed cavity, a vacuum pump, an air pumping pipe, a central control unit and a microwave generation device, wherein the vacuum pump is connected to the vacuum drying sealed cavity through the air pumping pipe having an air pumping valve, and an air exhaust hole having an air exhaust valve is formed in the vacuum drying sealed cavity. An intermittent microwave vacuum laundry drying method includes the following specific steps that the inner cavity of the vacuum drying sealed cavity filled with to-be-dried laundry is evacuated to vacuum, and the microwave generation device is used for moderately heating as an assistant; when the water on the to-be-dried laundry is fully boiled, the air pumping valve and the microwave generation device are closed; the air exhaust valve is opened, and the dry air from the outside enters into the inner cavity of the vacuum drying sealed cavity, the air humidity in the inner cavity of the vacuum drying sealed cavity is neutralized, and after completion in a short time, the air exhaust valve is closed again. The device and the method canprovide a low-cost, high-efficiency and low-energy drying solution for a microwave vacuum drying apparatus which processes high concentration moisture.