Primary renal non-Hodgkin's lymphoma is very rare in childhood. A six-year-old boy presented with bilateral non-obstructive multinodular nephromegaly and renal failure. Percutaneous needle biopsy showed large-cell lymphoma. The patient was started on chemotherapy. A right nephrectomy was done when systemic hypertension developed in the presence of a non-functional right kidney. Histopathologic examination revealed focal lymphomatous infiltration and xanthogranulomatous pyelonephritis which is an atypical form of chronic renal infection. The case is discussed in relation to previons reports.