The present invention relates to a method for screening for materials for promoting the differentiation of skin cells, comprising: a step of treating skin cells with a test material； and a step of checking the relative degree of the expression of the DUOX 1 gene in the skin cells treated with the test material in the previous step. The present invention also relates to a kit for screening for materials for promoting the differentiation of skin cells, comprising a device for checking the relative degree of expression of the DUOX 1 gene in skin cells. The present invention also relates to a composition which contains, as an active ingredient, a material for increasing the expression of the DUOX 1 gene to promote the differentiation of skin cells, moisturize the skin, improve skin barrier function, or alleviate or treat symptoms of atopic dermatitis.
