Abstract: SLE is not a rare disease in Iran. In the past 14 years, we have seen 503 cases. Renal manifestations were discovered in 317 of them (63%). The female ratio was 87%. All of them had proteinuria, but only 50% had a proteinuria superior to 500 mg per 24 hours. 60% had hematuria, 45% leucocyturia, and 42% had urinary casts. Serum creatinine was elevated in 16% of patients. Arterial hyper-tension was observed in 8% of cases. Kidney needle biopsy was performed in 187 patients. The light microscopy revealed: 80% WHO class 4, 13% class 3, 3% class 5 and 3% class 2. Two patients had normal histology. Comparison of other disease manifestations between nephritis and non nephritis patients revealed that CNS, ophthalmologic manifestations, and death were more frequent in nephritis group. The death was not related to renal lesions but to CNS involvement and microbial infections, especially the pulmonary tract. Comparison of the Iranian lupus nephritis with the Western lupus nephritis demonstrated a significant prevalence of WHO class 4 in Iranian patients. Their prognosis seemed to be better (better response to cytotoxic drugs, combined to steroids).