β-sitosterol acetate liposomes were prepared by thin-film ultrasonic method, and the effects of different incorporation concentrations on the particle size, PDI and storage stability of the liposomes were investigated, besides, the interaction between β-sitosterol acetate ester and phospholipids in the membrane was explored. The results showed that the size and PDI of the liposomes were consistent with that of the β-sitosterol liposomes under the same conditions when the addition amount of β-sitosterol acetate ester was 2 mg and 4 mg. It has good storage stability for low dosage of the β-sitosterol acetate ester liposomes at 4 ℃ for 30 days. The results showed that there was interactions between β-sitosterol acetate ester and P═O and (CH₃)₃N of phospholipids by FTIR. There was a stabilizing effect on liposome membrane structure at low dosage of β-sitosterol acetate ester by TGA.