Abstract: Employing an avidin-biotin complex im-munoperoxidase technique, it was faund that there was OKM5 but no OKM1 aratigen expression on keratiaocytes in lesions of seborrheic keratosis, verrucaus nevus, Bowen's disease, basal cell carcinoma, squamous cell carcinoma, malignant melanoma and sporo-trichosis as well as melanocytic nevus with inflammation.