The surface of wood flour was modified by three coupling agents: Titanate,Aluminate,and Al-Ti,respectively.The effects these coupling agents had on mechanical and rheological properties in wood-plastic composites were investigated.Scanning Electron Microscopy was used to analyze the effects of surface modification.The results showed that the Al-Ti compound improved the dispersion of the wood flour in the polymer matrix resulting in substantial improvement in the mechanical strength of the composites.The manufacturing process was also improved by adding Al-Ti compound coupling agent to the mixture.However,modification of wood flour with the coupling agents had insignificant effects on flexural modulus of the composites.