The utility model provides a flash tank steam recycle device, including flash tank, vapor collector, quadruple effect concentration evaporator, the outside of flash tank is covered with a vapor collector, and vapor collector passes through the pipeline and links to each other with quadruple effect concentration evaporator, is equipped with a steam flow control valve between vapor collector and thequadruple effect concentration evaporator, and one end of quadruple effect concentration evaporator still is connected with the vacuum pump, be provided with the steam delivery outlet on the flash tank, vapor collector's bottom sealless, the clearance between vapor collector and the flash tank is 5~10cm. The utility model discloses liquefying simultaneously and concentrated in -process, the direct steam that discharges the flash tank is carried to quadruple effect concentration evaporator, therefore the flash tank no longer has steam outwards to discharge, and concentrated post also no longerneeds plus steam, and this can economize on vapour 60%~70% in whole sugaring flow, improve the utilization ratio of heat energy, practices thrift the cost, and the reduction is to the influence of surrounding environment.