The invention discloses a light wood-plastic compound material for outdoor use. The wood-plastic compound material comprises the following components in parts by weight: 50-60 parts of thermoplastic resin, 70-82 parts of plant fiber powder, 3-5 parts of maleic anhydride grafted polypropylene wax, 1-2 parts of aluminic acid ester, 1-2 parts of lead stearate, 0.5-1 part of oxidized polyethlene wax, 0.5-1.5 parts of dioctyl phthalate, 3-3.5 parts of an ultraviolet ray stabilizing agent, 1-2 parts of an antioxidant, 0.5-1 part of zinc borate and 1.2-2.0 parts of toners, wherein the plant fiber powder is the mixture of coconut hull powder, cottonseed hull powder and pinewood powder, and the use ratio of the coconut hull powder to the cottonseed hull powder to the pinewood powder is 5:2: (1-1.5); the thermoplastic resin is the mixture of polypropylene and polyvinyl chloride. According to the light wood-plastic compound material, the characteristic that the ultraviolet ray resistant properties of coconut hulls and cottonseed hulls are higher is used, and the coconut hulls, the cottonseed hulls and the thermoplastic resin are combined, so that the comprehensive properties of the wood-plastic compound material which is finally obtained are excellent; the use amount of the ultraviolet ray stabilizing agent in the formula of the raw materials is small, so that the application range of the wood-plastic compound material for outdoor use is extended, and the wood-plastic compound material has favorable processing properties.