The improvement of heart function in a patient on hemodialysis with dilated cardiomyopathy by renal transplantation is herein reported. The patient was a 35-year-old woman. Hemodialysis had been initiated 3 months before, but she experienced difficulty with hemodialysis maintenance and exhibited congestive heart failure. The ejection fraction (EF) was decreased to 36.6% in the echocardiogram, and an intracardiac biopsy of the right ventricle showed myofiber degeneration and interstitial edema upon examination by light microscopy. She then underwent renal transplantation, and the postoperative recovery was almost uneventful. The cardiothoracic ratio decreased rapidly to around 40% after 1 month, although her body weight increased. The ejection fraction increased to 50% in the echocardiogram. An intracardiac biopsy of the right ventricle revealed disoriented myofibers, but myofiber degeneration improved, and no interstitial edema was present upon examination by light microscope. The electron microscopy showed that the intracellular edema had disappeared and other degenerative changes had also improved. The patient was discharged on the 44th postoperative day, with a serum creatinine of 1.3 mg/dl.