OBJECTIVE：To study the effects of different amounts of Euphorbiae Semen fatty oil in self-assembly micelles on intestinal absorption of 4 kinds of euphorbia （euphorbia L 1，L2，L3，L8）in rats. METHODS ：The self-assembled micelle solution containing 4 kinds of euphorbia was prepared by adding 4 kinds of euphorbia （40 mg/L）in excess ，using the fatty oil of Euphorbia Semen（0.2，0.4，1，4 g/L）and sodium deoxycholate as carriers. Totally 60 rats were collected to establish in-situ one-way intestinal perfusion model. Different intestinal segments （duodenum，jejunum，ileum，colon）were perfused with drug-containing intestinal perfusion fluid according to different dosage of Euphorbiae Semen fatty oil. HPLC method was adopted to determine the contents of 4 kinds of euphorbia in the intestinal perfusate before and after perfusion. The absorption rate constant （Ka）and apparent absorption coefficient （Peff）of 4 kinds of euphorbia in different intestinal segments were calculated. The ileum segment with better absorption was selected as the object to investigate and calculate the ac cumulative absorption of 4 kinds of euphorbia. RESULTS：The self-assembled micelles formed by different concentrations of fatty oil of Euphorbiae Semen could significantly increase the absorption of 4 kinds of euphorbia in different intestinal segments to different extents. When the dosage of Euphorbiae Semen fatty oil was 0.4 g/L，the intestinal absorption effect of 4 kinds of euphorbia were all the best ；the Peff was significantly increased，compared with no fat oil group （P＜0.05 or P＜ . According to the order of Ka and Peff of each intestinal ： segment in different fatty oil dosage groups ，the absorption 0531-89628590。E-mail：1310394709@qq.com effect of 4 kinds of euphorbia in each intestinal segment was the best in jejunum and the worst in colon. Compared with no fatty oil group ，when the amount of Euphorbiae Semen fatty oil w as 0.2-4 g/L，accumulative amount of 4 kinds of euphorbia in the ileum of rats increased significantly （P＜0.05 or P＜0.01）， and the highest in 0.4 g/L Euphorbiae Semen fatty oil group. CONCLUSIONS ：The self-assembly micelle s composed of Euphorbiae Semen fatty oil and deoxycholate can increase the absorption of euphorbia L 1，L2，L3，L8 in each intestinal segment to different extent，and the jejunum is the main absorption segment.