Xanthomas have been shown to occur in association with underlying lymphoproliferative disease, and sometimes are the result of lipid deposition in damaged or altered skin. Here in, we describe a case of eruptive xanthomas which developed in a patient suffering from mycosis fungoides. A 45-year-old Korean man presented for the evaluation of patches on the glans of his penis and on pretibial areas, which had persisted for a period of 3 years. Three months before the patient's admission, erythematous papules had developed on his trunk and extremities. Biopsies of lesions which had manifested as patches on the patient's pretibial areas and as papules on his right arm showed dermal infiltration of atypical lymphocytes, with epidermotropism and a diffuse infiltration of lipid-laden foamy cells. The histological findings were determined to be consistent with both mycosis fungoides and xanthoma.