Abstract: The effect of commonly used photo stabilizers on ageing resistance of wood plastic composites were investigated by analyzing the properties of WPC before and after accelerated weathering with added 6 different photo stabilizers. The results showed that photo stabilizers could effectively increase the ageing resistance ability of WPC, and reduce the mechanical properties during the aging process. The effect of different photo stabilizers on the decrease of WPC modulus of rupture have obvious difference during the aging process, hindered amine and benzophenone have greater effect than aziminobenzene. The effect of different photo stabilizers on the increase of water absorption rate of WPC also have significant difference during the aging process, the best was hindered amine, followed by benzophenon, and the worst was aziminobenzene. The effect of different photo stabilizers on the change of chromatic aberration showed no obvious differences.