Abstract:The chitosan used to be the clarification additive of grapefruit juice. By way of measuring with light transmission and absorbance，it was found that with the chitosan of deacetylation degree（DD=90 %），The optimum quantity of chitosan added in the juice to be the clarification additive was 0.6 g/L，The juice was treatedbook=113,ebook=119for 30 minute at 40℃.The pH value was the very pH of the original juice. After the components of the juice were detected，itwasshowedthat the nutrition such as total solubility solid contend，deoxidize sugar and Vc in the juice almost had no lost，pectin remove basically，protein reduce to some extent. And the juice had the good stability under the lower temperature. It was showed that the chitin has the lower cost on grapefruit juice clarification comparing with compound enzyme，pectin esterase and gelatin-tannins these three clarification methods.