Tungsten diselenide is an inorganic compound (WSe2).

It has a hexagonal crystalline structure. Every tungsten atom is covalently bonded to six selenium ligands in a trigonal prismatic coordination sphere, while each selenium is bonded to three tungsten atoms in a pyramidal geometry. Layers stack together via van der Waals interactions. WSe2 is a stable semiconductor in the group-VI transition metal dichalcogenides.