The invention discloses a high-temperature salt-containing wastewater concentration crystallization device and application. The device comprises a first concentration device, a second concentration device, a discharge device and a cooling device, wherein the first concentration device is adopted for primary concentration crystallization; the second concentration device is adopted for secondary concentration; the discharge device is used for discharging materials; the cooling device is used for providing a cooling function for the first concentration device; the first concentration device is aflash evaporation tank; and the second concentration device is a low-temperature salt evaporation device. By adopting the device, the number of solid-liquid separation devices is reduced, so that equipment investment cost and energy consumption can be reduced, meanwhile, the automatic degree is high, and labor cost is reduced. In addition, the device has the advantages that salts generated in thesystem can be rapidly separated, and the problem of secondary salt dissolution can be effectively avoided; and with the combination of a flash evaporation desalting technique and a low-temperature salt evaporation technique, low-grade heat energy carried by high-temperature salt wastewater can be sufficiently utilized, and energy consumption can be reduced.