Because omeprazole(OMP) is very unstable in aqueous condition, $OMP-{eta}-CD$, the inclusion complex of OMP and ${eta}-cyclodextrin({eta}-CD)$ was made and physicochemical properties of it were compared with those of OMP. Skin permeability of OMP and $OMP-{eta}-CD$ in propylene glycol vehicle and the reciprocal action of ${eta}-CD$ with various enhancers were examined through hairless mouse. Adhesive patches were prepared with polyisobutylene and the skin permeability and stability of OMP were investigated. The inclusion complex showed higher solubility and lower partition coefficient than OMP itself. DMSO, 1-methyl 2-pyrrolidone and sodium cholate had an enhancing effect. However ethanol and polysorbate 80 hardly showed the enhancing effect of OMP. When sodium lauryl sulfate and sodium cholate as enhancer were added in patch, the former case showed higher permeability of OMP.