Immunoglobulin A nephropathy (N.IgA) is the world most common glomerular disease; 15-50% of patients develop loss of renal function in 10-20 years, and the rest remission or mild proteinuria/ hematuria. The optimal treatment is uncertain. Our aim was to develop evidence-based recommendations through research in Medline, Embasse, Lilacs and Cochrane Central Register of Controlled Trials. The study-quality was independently assessed by the reviewers following the Cochrane Renal Group checklist: randomization, blinding, intention-to-treat analysis and follow-up period. Levels of evidence and grades of recommendation were assigned according to Center for Evidence-Based Medicine, Oxford. Two approaches were considered: Immunosuppressive therapy (corticosteroids, cytostatics, cyclosporine A, mycophenolate-mofetil): Level I a, grade A. -Combined suppressive therapy in adults. Corticosteroids plus cytotoxics drugs (cyclophosphamide/azathioprine): Level II b, grade B. In children with severe IgA nephropathy: Level II b, grade D. Cyclosporine and mycophenolate- mophetil: Level II b, grade C. Cyclosporine and mycophenolate-mophetil: Level ll b, grade C. -Non immunosuppressive therapy: reninangiotensin converting enzyme inhibitors (ACEI) and/or angiotensin II receptor blockers (ARB), fish oil, statins, antiplatelets and tonsillectomy. ACEI and/or ARB, in patients with proteinuria ≥ 1 g: Level I a, grade A. In children with moderate proteinuria: ACEI and/or ARB with close monitoring of renal function and serum potassium level: Level II b, grade B. Antiplatelet as supportive treatment: Level I a, grade C. Fish oil in addition to ACEI or ARB in patients with mild histological lesions: Level II b, grade B (Not in children). Statins: no evidence to recommend these drugs in children. In patients > 5 years with nephrotic syndrome and hyper-cholesterolemia, use statins with close monitoring of serum creatine-kinase. There is no evidence to recommend tonsillectomy.