Abstract: Tricaprylin was prepared by direct esterification method with caprylic acid and glycerol as raw material and cation exchange resin HND-6 as catalyst.The standard curve of tricaprylin used for the qualitative and quantitative analysis was established by high performance liquid chromatography and the regression equation was y=974 980x+1 197(R²=0.999 0).The effect of reaction time,reaction temperature,molar ratio of caprylic acid to glycerol and catalyst loading addition amount on the conversion rate of tricaprylin was investigated by single factor test.Response Surface Methodology (RSM) adopting Box-Benhnken Design (BBD) principle was used to further optimize the preparation processing conditions on the bases of single factor test.The results showed that the optimal conditions were as follows:reaction time 7 h,reaction temperature 113℃,substrates molar ratio 5.3:1,catalyst addition amount 65%(based on mass of glycerol,equivalent to 6.99% of the total substrates mass).Under the above conditions,the conversion rate of tricaprylin reached to 87.52%,which was nearly consistent with the predicted value.