近年来，多糖的研究引起了国内外许多学者极大的兴趣。多糖不但能治疗机体的免疫系统受到严重损伤的癌症，又能治疗多种免疫缺损疾病。多糖的免疫疗法已经给近代肿瘤、艾滋病及其它疾病的治疗开辟了新的方向。由于分子生物学和分析新技术的高速发展，多糖的分离和分析手段也取得了很大的进展。使得科学家更为直接有效地探索生命现象的无穷奥秘。目前，多糖研究的关键在于产品质量标准的制定，尤其是特异指标的制定，以及多糖作用机制的研究等方面。本文主要从分布、提取、分离、纯化、检测和结构鉴定等方面综述了天然多糖的研究情况。

The research of polysacchides has aroused great interest during recent years. polysacchides is not only used in the treatment of cancer but also of immunodeficiency disorders. Polysacchides as immunomodulation agents ard being investigated for potential uses in neoplasm and AIDS et al. With the rapid evolution and adoption of molecular biology and new analytical techniques, the methods of isolating and analyzing polysacchides develop greatly too. So far establishing product - quality - standal is the key point of Polysacchides researcn, especially for the characteristic index and the action mechanism of Polysacchides. This paper reviewed the reserch on natural Polysacchides from its distribution, extraction, isolation, purification, examination, identification and so on.