Kaposi sarcoma (KS) is a vascular neoplasm mainly affecting the skin of the limbs that has previously been associated with rheumatoid arthritis (RA). When compared with the RA patients treated with corticosteroids and immunosuppressive drugs, the reported number of KS in RA patients was very rare. Although the exact mechanisms of developing KS in RA patients are unclear, some drugs which include corticosteroid have been suggested as an etiological factor in previous case reports of RA and KS. We report, here in, another case of KS associated with the initiation of leflunomide in a patient with RA.