Primary renal lymphoma is a controversial and rare disease. There is no agreement whether or not it is an initial manifestation of a rapidly systemic disease. Most reported cases are questionable because of incomplete staging and lack of autopsy studies. Herein, we present a 71-year-old woman, initially diagnosed with primary non-Hodgkin lymphoma of the kidney, but was lost 4 months after radical nephrectomy due to systemic disease despite aggressive chemotherapy, and suggest that, the kidney of the patient was the initial presenting site of a rapidly progressive systemic disease.