The invention provides a growth method of zinc selenide, which comprises the following steps: a. Putting zinc into a crucible in a chemical vapor deposition furnace, replacing air in the deposition furnace with argon, and vacuumizing until the vacuum degree is 3000Pa-10000Pa; b, heating a deposition chamber in the chemical vapor deposition furnace to a deposition temperature of 700 DEG C to 800 DEG C, and heating the crucible to an evaporation temperature of 650 DEG C to 700 DEG C; c, respectively introducing gas into the crucible and the deposition chamber to carry out a vapor deposition reaction of zinc selenide, introducing argon into the crucible, and introducing argon and hydrogen selenide into the deposition chamber to make the deposition rate of zinc selenide be 50-150 [mu]m/h; andd, after the reaction is finished, maintaining the same pressure and gas flow as those in the deposition process, continuously heating the deposition chamber to 50 DEG C to 170 DEG C, keeping the temperature constant for the first time, cooling to 500 DEG C to 650 DEG C, keeping the temperature constant again, and cooling the reaction product to room temperature to obtain the zinc selenide product. The growth method of zinc selenide provided by the invention can be used for producing the polycrystalline zinc selenide material with large size, thickened size and high optical performance.