A 23 year-old male was investigated for hypertension, moderate renal insufficiency, persistent proteinuria and bilateral small kidneys. The renal pathological features were diagnostic with greatly enlarged glomeruli (the mean diameter was 325 μm, which was approximately two times larger than normal glomeruli), indicating oligomeganephronia (OMN). He also showed malrotated kidneys, expanded extrarenal pelvis, and hearing loss. Thus, these clinical and pathological features aided in diagnosing the renal disorder as OMN. This is a very rare case of OMN, which did not advance to end-stage renal failure as an adult. We believe that multiple anomalies might be suggestive findings of OMN in patients, such as renal insufficiency, persistent proteinuria, and bilateral small kidneys.