Misoprostol is a derivative of prostaglandin E1. It has a strong inhibitory effect on gastric acid secretion and a contractile effect on the pregnant uterus. In addition, misoprostol has the pharmacological activity of E-type prostaglandins, which can soften the cervix, enhance uterine tension and intrauterine pressure. The sequential use of misoprostol with mifepristone has become one of the main methods of mid-term induction of labor. It can better replace surgical operations such as curettage and amniocentesis. The success rate of abortion is about 96.1%. It is a safe and effective method of induction of labor. Misoprostol is the first PGE (prostaglandin E) derivative used in clinical practice. It has obvious effects on various ulcers (except duodenal ulcers). However, it is expensive and is currently generally used as a second-line drug for the treatment of ulcer disease, mainly for refractory ulcer disease or recurrent ulcers.