Japan wax (木蝋 Mokurō), also known as sumac wax, sumach wax, vegetable wax, China green tallow, and Japan tallow, is a pale-yellow, waxy, water-insoluble solid with a gummy feel, obtained from the berries of certain sumacs native to Japan and China, such as Toxicodendron vernicifluum (lacquer tree) and Toxicodendron succedaneum (Japanese wax tree).

Japan wax is a byproduct of lacquer manufacture. The fruits of the Toxicodendron trees are harvested, steamed, and pressed for the waxy substance which hardens when cool. It is not a true wax but a fat that contains 95% palmitin. Japan wax is sold in flat squares or disks and has a rancid odor. It is extracted by expression and heat, or by the action of solvents.