A 45-year-old man underwent heart transplantation due to dilated cardiomyopathy. Cyclosporine, 2 mg/kg per day, was intravenously givell postoperatively. As central neurotoxicity signs that were included pin-point pupil, no light reflex, coma, were presented at 8 postoperative hours, cyclosporine was decreased to 1 mg/kg er day. At that time the cyclosporine level was 345 $mu extrm{g}$/L, the serum creatinine level was 1.8mg/dl and the serum magnesium level was within normal limit. He awaked at 31 postoperative hours and all sign of cyclosporine-induced central neurotoxicity was resolved after postoperative days. He was discharged without sequale at postoperative day 28.