Organic solvents have been used as vehicle for cosmetics and percutaneous pharmaceuticals in skin. We performed X-ray diffraction measurement on applying a solvent, ethanol, to hairless mouse stratum corneum. We found that the diffraction peak intensities for the structures formed by lamellae and soft keratins decreased, while that for the hydrocarbon-chain packings slightly decreased. In addition the intensity of ethanol in the stratum corneum increased. After evacuating ethanol solution from the stratum corneum, all of the structures were largely regenerated.