Three kinds of nano-zirconia slurries were made by surface chemical modification methods and the slurries were respectively used to prepare styrene-acrylic emulsion,to improve hardness and wear resistance of water-borne styrene acrylate wood coatings.Then the effect of surface modification methods on nano-zirconia slurry properties as well as the hardness and wear resistance of styrene-acrylic wood coatings were investigated.The results showed that the slurries showed excellent performance like small particle size,low viscosity and good stability when polyacrylamide,polyethylene glycol and octylphenol polyoxyethylene ether were used as modifiers.When 1% of the nano-zirconia slurry was added into water-borne styrene acrylate wood coatings,the abrasion value of the coating film was 0.069g/100 rwith 1 800 rof abrasion cycle and 2H of hardness.