The therapeutic approach to patients with membranous lupus nephropathy (MLN) remains controversial. We have attempted combination therapy for MLN. Five patients with MLN (WHO class Va and Vb) and nephrotic syndrome were treated with 1 g methylprednisolone intravenously for 3 consecutive days followed by daily prednisolone at the dose of 30-40 mg plus cyclosporine at the dose of 100-200 mg and angiotensin receptor blocker(40 mg of valsartan). Initial dosage prednisolone was given for 1 month, and then tapered gradually in terms of dosage and interval. These patients were followed up for a minimum of 12 months. Complete remission was obtained in 4 patients after a mean of 7.3 +/- 2.1 months, and partial remission was obtained in the remaining patient. Daily prednisolone dosage significantly decreased from a baseline mean of 0.69 +/- 0.11 mg/kg to a mean of 0.10 +/- 0.02 mg/kg at the last follow-up. Lupus activity, as measured by SLE disease activity index, significantly decreased in all patients. Serum creatinine level and blood pressure remained stable. It was concluded that quadritherapy, including intravenous methylprednisolone, prednisolone, cyclosporine, and angiotensin receptor blocker, was beneficial in inducing remission of nephrotic syndrome, reducing lupus activity, and sparing prednisolone dosage with an acceptably low risk for side effects.