Renal osteodystrophy is a common long-term complication of end-stage renal disease. Involvement of the jaws is common and radiographic alterations are often one of the earliest signs of chronic renal disease. However, marked enlargement of the jaws is a rare complication of renal osteodystrophy. A case of localized asymptomatic enlargement of the mandible in a 38-year-old woman with chronic renal failure is presented. The clinical, radiographic, and histological findings were consistent with renal osteodystrophy. To our knowledge, this is the third case of localized mandibular enlargement of renal osteodystrophy reported in the English-language literature.