ZrO2?TiO2 composite catalysts were prepared by method of coprecipitation. The crystal morphologies of samples were characterized, specific surface area and pore size distribution of samples were identified, the acid properties of catalysts were identified, and catalytic performances were investigated by esterification of citric acid with n-butyl alcohol. The results showed that when ZrO2 was 25%(?) among the complex oxide, sample ZrO2?TiO2 was shown amorphous, its specific surface area of 239.6 m2/g, with B acid and L acid centres for NH3 adsorption capacity of 670 μmol/g. Esterification of citric acid with n-butyl alcohol was investigated over 25%ZrO2?TiO2 as catalyst. The conversion rate of citric acid reached to 96.6% and selectivity of trbutyl citrate exhibited is 98.2% while the suitable reaction conditions are reaction temperature of 115℃ and balanced time of 90 min. After reaction 5 times, conversion rate of citric acid keeps higher than 80%, and selectivity of tributyl citrate is about 98%.