OBJECTIVE To study the correlation between penetration enhancement effect and transepidermal water loss(TEWL)values of essential oils(EOs)from traditional Chinese medicine(TCM).METHODS The amount of 3 kinds of glycosides(geniposide,gentiopicroside,paeoniflorin)and their oil-water partition coefficient were determined by HPLC.The penetration enhancement effect of the five EOs from Gaoliangjiang(Alpiniae Officinarum Rhizoma,AOR),Ganjiang(Zingiberis Rhizoma,ZR),Bohe(Menthae Haploca-lycis Herba,MHH),Hujiao(Piperis Fructus,PF)and Wuzhuyu(Euodiae Fructus,EF)on geniposide,gentiopicroside,and paeoniflor-in were performed by the modified Franz diffusion cell method with the abdominal skin of rats.The TEWL values were measured to evalu-ate the effect of the five EOs on the skin barrier function of rats.The correlation between penetration enhancement effect of EOs and their effect on skin barrier function was investigated by correlation analysis.RESULTS AOR oil,ZR oil,MHH oil,and PF oil could im-prove the absorption of the three glycosides and reduce skin barrier function of rats.The results of correlation analysis showed that the penetration enhancement effect of EOs was significantly related to TEWL values following dermal administration of EOs.CONCLUSION TEWL measurement technology provides a more convenient method for the selection of penetration enhancers.