The invention provides a vertical vacuum crystallization device. The vertical vacuum crystallization device comprises a crystallization part and a condensing part, wherein the crystallization part islocated below the condensing part and comprises a crystallization section cylinder, an outer flow guiding cylinder, a central flow guiding cylinder, a bottom stirrer, a secondary stream rising cylinder, a circulating cylinder, an inner circulating channel and an outer circulating channel; and the condensing part comprises a condensing section cylinder as well as an overflow weir, a first water baffling cap, a liquid baffling ring and a second water baffling cap which are sequentially arranged in the condensing section cylinder from top to bottom. The vertical vacuum crystallization device hasthe advantages that a heat exchanger does not need to be replaced, and the problems that the inner surface is seriously scaled, and the scale is difficult to clean are prevented; an vacuum processingpressure is similar to a solution steam partial pressure, and the operation is relatively stable; the crystallization part and the condensing part form equipment, so that a secondary steam flow path is shortened, and the leakage of leaking points caused due to the connection of pipelines is eliminated; by utilizing the inner circulating channel, the high-saturability region in the crystallizationpart is eliminated, and the saturability at each site is relatively uniform and low; and by utilizing the outer circulating channel, the excess crystallization is eliminated; and meanwhile, products with relatively narrow particle size distribution can be elutriated.