Abstract: In this paper, the feasibility of skin permeation for lidocaine and pressure sensitive adhesive(PSA)tape formulation containing lidocaine for skin local anesthetic were assessed. Firstly,in vitro skin permeation of the molecular and ionic forms of lidocaine from water and silicone fluid suspensions was measured using a side- by-side two diffusion cells and excised hairless rat skin.Secondly, PSA tape containing lidocaine was prepared by a general casting method using styrene-isoprene─styrene block copolymer. The in vitro release and skin permeation were evaluated and compared with that of Japan marketed xylocaine jelly. The effect of lidocaine concentration on the steady-state flux of skin permeation from 10%to 60%lidocaine PSA tapes was also evaluated.