Abstract:Most patients with X‐linked dominant chondrodysplasia punctata (X‐DCDP) have whorled, thick, or spiky adherent hyperkeratosis on their whole body. Histopathologically, there are large keratotlc plugs of hair follicles where calcium deposits. This is the characteristic finding in this disease. We performed histopathologic examination of skin specimens from two newborn babies with X‐DCDP. The desquamated thick scales from the hyperkeratotic lesions had calcium in the center of the keratotic plugs. Histopathologic examination of thick scales is easy and helpful in diagnosing X