The inventiondiscloses avisual three-temperature-area gallium selenide single crystal growth device and method, and relates to a crystal growth device and method. The invention aims to solve technicalproblems of uneven stress distribution and low transmittance of gallium selenide single crystal grown by using a bridgman-stockbarger method in the prior art. The device comprises an outer sleeve, aninner sleeve, a heating resistance wire, an annular cavity, a reflection film, a temperature thermocouple, an end cap, and a heat preservation plug; the reflection film is attached to the inner wallof the outer sleeve; the annular cavity between the outer sleeve and the inner sleeve which are prepared from transparent materials is a vacuum cavity; and the heating resistance wire is arranged in the annular cavity. The method comprises the following steps: placing gallium selenide crystal seeds in a PBN boat, obliquely sealing in a vacuum quartz tube in a suspended manner, placing the quartz tube in the middle of the growth device, adjusting the temperature gradient of the three temperature areas, melting a part of the crystal seeds, fully melting polycrystal materials, then cooling for curing, and finally cooling to the room temperature to obtain allium selenide single crystals. The transmittance of the single crystals is 64%-66%, and the single crystals can be applied in civil and national defense fields.