The invention relates to providing a method for more conveniently evaluating stratum corneum condition. A stratum corneum sheet is contacted with a solution of a water-soluble dye, and the staining intensity or fluorescence intensity is measured to allow convenient evaluation of the stratum corneum condition. There is further provided a method for evaluating the ameliorating effect of a cosmetic or cosmetic treatment on the stratum corneum, by implementing the method for evaluating stratum corneum condition using a water-soluble dye according to the invention.
