Intravascular large B-cell lymphoma (IVLBCL) is a rare entity of lymphoma. We report a case of IVLBCL presenting as renal dysfunction which was diagnosed by renal biopsy. Histopathological examination of the renal biopsy specimens showed dissemination of lymphoma cells throughout the glomerular capillary lumens. The cells were CD5-, CD10-, CD20+, BCL2+, BCL6+, and MUM-1+. Rituximab-chemotherapy was performed and complete response was achieved. With the accumulation of cases, establishment of a treatment strategy for IVLBCL is expected in the future. We could perform early diagnosis by renal biopsy and were able to achieve long-term remission by rituximab combination chemotherapy.