目的　研究对墨西哥仙人掌的粗多糖的提取及糖含量的测定。方法　酒精沉淀法提取粗多糖 ,利用分光光度法测定糖含量。结果　沉淀 48～ 6 0h ,酒精用量 6 5倍 ,为提取仙人掌粗多糖方法。仙人掌酸提物的糖含量 46 19%,水提物的糖含量为 43 5 2 %。结论　酸提物中粗多糖的阿拉伯糖含量高于水提物中粗多糖的阿拉伯糖含量。 Objective To study the extraction and sugar content of crude polysaccharide from Mexican cactus. Methods Alcohol precipitation was used to extract crude polysaccharides and the content of sugar was determined by spectrophotometry. Results Precipitation 48 ~ 60h, alcohol consumption 65 times, for the extraction of cactus polysaccharide method. The sugar content of the cactus acid extract is 46 19%, and the sugar content of the water extract is 43 5 2%. Conclusion The arabinose content of the crude polysaccharide in the acid extract was higher than the arabinose content of the crude polysaccharide in the aqueous extract.