Abstract: OBJECTIVE To investigate the effect of different penetration enhancers on the external transdermal absorption characteristics of the pharmacodynamic components of daphnetin in post-crosslinking Daphnes Giraldii Cortex gel plaster and screen out the best penetration enhancers. METHODS In vitro transdermal test was carried out with mouse skin and Strat-M™ membrane as the penetration barrier by Franz diffusion cell method. Using the cumulative penetration rate per unit area of daphnetin within 72 h as the evaluation index, by single factor experiment and orthogonal experiment to investigate the promoting effect of borneol, menthol and camphor on the daphnetin. RESULTS When in vitro mouse skin and Strat-M™ membrane were used as transdermal barrier, the cumulative transdermal flux per unit area was 33.85, 15.96 μg·cm^-2 for 72 h, and the steady transdermal rate was 4.451 2, 2.394 5 μg·cm^-2·h^-1. The infiltration multiple was 4.255 0 and 1.746 4. CONCLUSION The best penetration enhancer of post-crosslinking Daphnes Giraldii Cortex gel plaster is 1% menthol, 1% borneol and 2% camphor.