Desmoplastic malignant melanoma(DMM) is an uncommon variant of malignant melanoma featuring a proliferation of spindle cells with pronounced desmopaasia. DMM commonly occurs on the sun-damaged skin such as head and neck in older persons, and it can be associated with lentigo maligna. We report an unusual case of desmoplastic malignant melanoma that developed de novo on the trunk in a young patient.