Radix Inulae is used as a gastric and antibacterial agent in traditional Chinese and Tibetan medicines. Most of its chemical constituents have been identified and include a series of sesquiterpenes with various carbon skeletons such as: eudesmanolide, elemanolide, germacranolide, sesquicaranolide, guaianolide and humulane. Certain organic solvent fractions and sesquiterpenes from Radix Inulae have been found to significantly inhibit the growth of tumor cell strains in vitro. They also show antibacterial, cardiovascular and hypoglycaemic as well as insulin-sensitization activities. The present review summarizes research on the chemistry and biological activity of Radix Inulae.