Porokeratosis includes a group of heterogenous disorders that represents distinct clinical subtypes of the same genetic pattern. Although entire pathogenesis of porokeratosis still remains unknown, certain factors including ultraviolet radiation and immunosuppression are suggested to be some of the factors inducing this disorder. Eruptive disseminated porokeratosis is a recently described form of porokeratosis, which frequently occurs in the presence of immunosuppresion or malignancy. The authors report here a unique case with sudden onset eruptive disseminated porokeratosis associated with diabetes mellitus.