We encountered a disseminated sporotrichosis patient with polyarthritis and progressive skin ulcers, who had been previously treated with prednisolone, tocilizmab, tacrolims, and cyclophosphamide under the diagnosis of rheumatoid arthritis in another hospital. Making the diagnosis of leukocytoclasticvasculitis based on the clinical observation of skin ulcers, we intensified immunosuppressive therapy. Unfortunately, the patient developed septic shock. Blood culture revealed that the pathogenic organism was sporothrixschenckii. Any case of intractable arthritis or skin ulcers, which does not improve, despite adequate immunosuppressive therapy, is likely to be suspicious of sporotrichosis.