Involvement of testis by malignant lymphoma is rare in young age, comprising only 2% of testicular cancers under 50 years old and 25% of over 50 years old. Testicular lymphoma is frequently bilateral and has a poor prognosis. Testicular lymphoma has a propensity to involve the skin, the central nervous system, Waldeyers ring and adjacent structures. Renal involvement in lymphoma is often manifested as multinodular masses, whereas diffuse renal infiltration is less freguent. Most often, renal involvement of malignant lymphoma is asymptomatic. Of the reported cases of renal insufficiency secondary to diffuse renal infiltration with lymphoma, few have presented with acute renal failure. We present a patient with acute renal failure secondary to diffuse bilateral renal infi1tration and unilateral testicular non-Hodgkin's lymphoma.