This is a flash sintering furnace with preheating function, equipped with a flash sintering power supply, through the electrode flange to introduce the current to the sample to apply an electric field, to achieve the Electric Current-Assisted Sintering (ECAS) processes, compared with the traditional ceramic sintering process, has the advantages of ultra-fast, energy-saving and conducive to the preparation of fine-grained ceramics, can be widely used in the flash sintering process of various ceramics.