A three-tank-type small-sized soybean milk machine is characterized in that the soybean milk machine comprises a high-temperature and high-pressure gas generation tank, a raw material heating pressure tank and a flash evaporation emusifying tank; three tank bodies are communicated with one another by a first conveying pipe and a second conveying pipe; the raw material heating pressure tank is internally provided with a rotational flow tube arranged obliquely; the raw material heating pressure tank is communicated with the high-temperature and high-pressure gas generation tank by the second conveying pipe; the flash evaporation emusifying tank is internally provided with a flash evaporation nozzle which is arranged on a flash evaporation straight pipe; the flash evaporation straight pipe is communicated with the raw material heating pressure tank by the first conveying pipe; the position at the upper end of the tank body corresponding to the flash evaporation nozzle is provided with a negative pressure exhaust cylinder; the flash evaporation nozzle is provided with a clearance adjusting rod; and the clearance between the nozzle cover disc and the flash evaporation straight pipe outlet is 0.2mm and can be adjusted by the clearance adjusting rod. The three-tank-type small soy milk machine has compact structure, convenient manufacture and easy operation, replaces all functions (heating, sterilizing and flash evaporating used for removing fishy smell and the human harmful substance, emulsifying and the like) of imported equipment by three tanks.