In Lithuania renal biopsies (RB) have become routine since 1995. Our study attempted to analyze RB for 5 years in Lithuania. We analyzed data of adult patients who underwent native kidney biopsies in 6 renal units in the period between 1995 - 1999. It accounted for 62.5% of all kidney biopsies, done throughout Lithuania. All biopsy specimens were examined by the same pathologist using light- and immunofluorescence microscopy. A total of 316 renal biopsies was analyzed; males : females 1.8 : 1. The mean age was 41.4 +/- 16.7 years. The most common indications for biopsy was nephrotic syndrome (29.1%) and urinary abnormalities (27.8%). After exclusion of inadequate biopsies in the remaining 280 RB, primary glomerulonephritis (GN) accounted for 68.7% and secondary GN for 19.5%. The most frequent forms of primary GN were membranoproliferative GN and immunoglobulin A nephropathy (17.9% and 15.4%, respectively), followed by membranous nephropathy (7.1%) and focal segmental glomerulosclerosis (6.8%). The main indication for renal biopsy in Lithuania was nephrotic syndrome, which was followed by isolated urinary abnormalities. The leading type of kidney damage was primary glomerulonephritis, which was 2.4 times more frequent in males than in females. The most frequent form of primary glomerulonephritis was membranoproliferative GN, with dominance in males. Immunoglobulin A nephropathy was the second form of primary GN according to the frequency.