Abstract: The effects of preparing conditions of KGM-TiO2 composite films were studied. Based on tensile strength and elongation at break,the influence of the concentration of KGM sol,the amount of glycerin,pH and drying temperature of composite films were investigated. The preparation process of KGM-TiO2 composite films was optimized by single factor experiment and response surface methodology while the effects of the ratio of composite thin films doped with TiO2 was also studied. A regression model for each of the film properties was developed. The optimal preparing conditions were KGM concentration 1%,glycerin amount0.45%,pH10 and drying temperature 71℃. The incorporation of TiO2 could effectively improve the elongation at break and the mechanical propeties of KGM thin films with the best value 0.003%.