Abstract: With poplar wood flour as filling material, polyvinyl chloride (PVC) as matrix materials, by adding bamboo charcoal and chitosan, bamboo charcoal and chitosan modified wood powder/PVC wood-plastic composites were prepared by extrusion molding. The surface micro morphology of the composites was observed by SEM. The thermostability and the functional group variation of the composites were analyzed by comprehensive thermal analyzer and FTIR, respectively. And the mechanical properties of the wood flour/PVC wood-plastic composites were also measured. The results show that the compound of bamboo charcoal and chitosan could effectively improve the interface reaction and interface compatibility between wood flour and PVC and increase the mechanical properties of the composites. The tensile strength, impact strength, flexural strength and flexural modulus of the composites added bamboo charcoal and chitosan increase 14.6%, 28.8%, 11.1% and 4.85% compared with those of wood flour/PVC composites, respectively, and the micro interface defect of the composites was less. Bamboo charcoal could enhance the thermostability of the composites. The compound of bamboo charcoal and chitosan could increase the amount of hydroxyl, amidogen and methylene groups in the composites, and decrease the adhesive strength of carbon-chlorine bond, which will reinforce the interface bonding force between wood flour and PVC of composites.