An aryl elemental selenium compound synthesis method comprises the following steps: taking copper compound as a catalyst; under the existence of an oxidant and an organic ligand, allowing aryl group aryl boric acid compound to react with the elemental selenium in a reaction solvent; obtaining the aryl elemental selenium compound through further manufacturing. The synthesis method is simple in operation, good in catalysis efficiency, and relatively high in product purity, and has a great scientific research value and an excellent industrialization prospect.