The invention relates to a microwave steam explosion device which comprises a feed-inlet ball valve, a steam explosion tank, a buffer vessel, and a gas condensation and recovery system, wherein the steam explosion tank is sleeved with a microwave oven cavity, the steam explosion tank is provided with a pressure gauge, a thermometer and a safety valve, and the steam is fed into the gas condensation and recovery system. The microwave oven cavity adopts an integral control system and a staggered and resonant arrangement design on industrial double-magnetrons, continuous output microwaves are obtained by using a high frequency close-loop feedback and magnetron anode current control mode, and through contactless infrared temperature control and contactless optical pressure monitoring, the real-time display of a pressure-temperature-time-power curve and a temperature-pressure-time curve can be realized on an ultra-large touch LCD (liquid crystal display) screen. The device provided by the invention has the advantages that the stream indirect heating is replaced with the microwave direct heating, so that 4 / 5 of the heating time is shortened, therefore, the problem of high energy consumption existing the existing steam explosion technology can be solved, and the requirements of solid materials such as foods and traditional Chinese medicines, and the like for water quality are satisfied; and in addition, because of adopting automatic control, the device is easy to operate, and has good economic and application prospects.