Keratinocytes play an important role in the inflammatory response of the skin. UVB stimulates keratinocytes to secrete several cytokines. To our knowledge, there are no reports that have examined which layer or cell type is responsible for producing these cytokines. Thus, in this study we performed immunohistochemical experiments to determine the potential cells or layers that express interleukin (IL)-1 and IL-6. The results show that the expression of IL-1α and IL-6 was induced 3 and 6 h after irradiation, respectively. Furthermore, IL-1α was maximally expressed earlier than IL-6, suggesting that IL-1α exists in the cytokine cascade of the UVB response upstream of IL-6. In addition, IL-1α expression began in the upper layers of the epidermis, whereas all layers expressed IL-6. This study provides further insight into the roles of cytokines in UVB-induced skin inflammation.