The clinical presentation and natural history of 428 patients with biopsy-proven primary glomerulonephritis were reviewed. Minimal change glomerulonephritis presented with the nephrotic syndrome and followed a benign course. Membranous glomerulonephritis took a slow downhill course. HBs antigenaemia was present in 30% of patients with membranous glomerulonephritis. Mesangiocapillary glomerulonephritis often presented with mixed nephritic-nephrotic syndrome and had a bad prognosis. No type II variant was detected. Mesangial IgA glomerulonephritis commonly presented with abnormal urinary sediments although 2.5% of adults presenting with the nephrotic syndrome without glomerular insufficiency had mesangial IgA disease. Mesangial IgA glomerulonephritis was an important cause of end-stage renal failure in Hong Kong.