Abstract: Objective:To study the effect of laccrocapram on percutaneous absorption of aspirin cream across mice skin in vitro.Methods:Fluids were collected by using Franz diffusion cells after permeation through the skin of mice.And the per square centimeter's accumulative permeation quantity,steady percutaneous speed and permeation coefficient were determined by ultra-violet spectroscopy.Results:Steady percutaneous speed of acetyl salicylic acid cream with 5% and 10% laccrocapram increased 10.6% and 25.0%,respectively.Conclusions:Different concentrations of laccrocapram can increasing permeation of acetyl salicylic acid.The permeation from emulsion base conformed to Higuchi equation.