Abstract: OBJECTIVE To study the preparation of Cangai oil transfersomes and investigate its release behavior in vitro. METHODS Cangai oil transfersomes was prepared by using the thin-film ultrasonic method and taking sodium cholate and propanediol as membrane softeners. The encapsulation rate was determined by petroleum-ether-extraction and UV method. The release and transdermal penetration behavior of Cangai oil transfersomes in vitro were investigated by HPLC while eugenol was detected as the index component. RESULTS The average particle size of Cangai oil transfersomes prepared by the preferred formulation was (149±4.37) nm， and the polydispersity index was 0.189±0.024， encapsulation rate was (89±2.50)%， and the zeta potential value was (-42.95±1.78)mV. The results of release in vitro showed that the release of Cangai oil reached a steady state at about 6 hours， while Cangai oil transfersomes and Cangai oil liposomes continued to release for 12 hours. The results of percutaneous permeation in vitro showed that Cangai oil transfersomes had higher cumulative permeation than Cangai oil liposome and Cangai oil from 6 hours (P<0.05). CONCLUSION Cangai oil transfersomes prepared by optimized prescription has an integrated appearance and narrow particle size distribution. It not only increases the solubility of Cangai oil， but also has a certain slow-release effect， which is a potential transdermal drug delivery carrier. It can also significantly increase the transdermal efficiency of Cangai oil after transdermal administration in vitro， and it is a transdermal drug carrier with good potential.