The clinicopathological findings of perforating dermatitis in two young and two adult cats are described. In all cases, the lesions were characterized by single or multiple papules and plaques, 0.5-3.0 cm in diameter, each containing a central, firm, exophytic, cone-shaped, yellow-orange keratotic plug, tightly adherent to the underlying skin. Removal of the protruding material was associated with bleeding and left the ulcerated surface exposed. In one case, the lesions showed a linear configuration and identical lesions occurred on the suture sites following biopsy. Histopathologically, the diagnosis was straightforward because of the presence of vertically orientated collagen bundles extruded from ulcerated, concave-shaped invaginations of the skin. In two cases, vitamin C administration failed to resolve the disease. In two cases, methyl-prednisolone acetate was used to manage relapsing episodes and vitamin C helped to reduce glucocorticoid requirements. In one case, treatment with methyl-prednisolone acetate only appeared to be curative. The fourth case was lost to follow-up immediately after the diagnosis.