Intravascular lymphoma is an uncommon disease in the skin and central nervous system. Here, we present a 75-year-old woman who suffered from severe pain, swelling and erythema bilaterally over her thighs with intermittent fever for over 10 days. Skin biopsy showed medium-sized neoplastic cells with atypical nuclei and arranged in a discohesive pattern with aggregation in vascular lumens. Under the impression of lymphoma, immunohistochemical staining was performed and revealed positive staining for CD45 and CD20 in the tumor cells. Therefore, intravascular B-cell lymphoma was confirmed. The patient had relatively normal brain, chest, and abdominal radiography. Blood smears and bone marrow aspirates showed no abnormal cells. The patient was given one cycle of cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisolone chemotherapy. After one cycle of chemotherapy, the erythema disappeared and the fever subsided. To date, no tumor relapse has been seen after seven months of follow up.