A 30-year-old female developed fever and multiple lymphadenopathy in September 2011. Her symptoms improved with antibiotic treatment. However, she again presented with fever and multiple lymphadenopathy in December 2011. In addition, she suffered from nephrotic syndrome with severe edema. She was therefore hospitalized to undergo detailed examinations. Renal biopsy revealed endocapillary proliferative glomerulonephritis. Since her renal function deteriorated rapidly, she was given steroid pulse therapy with methylprednisolone, followed by maintenance therapy with prednisolone. After treatment, her renal function improved but multiple lymphadenopathy persisted. Biopsy of a left axillary lymph node was then performed and revealed angioimmunoblastic T-cell lymphoma (AITL). She received CHOP therapy but showed no response. Therefore, she was given ESHAP therapy. A partial response was achieved and the nephrotic syndrome also resolved completely. We report this extremely rare case of renal dysfunction due to endocapillary proliferative glomerulonephritis complicated by AITL.