Post-transplantation diabetes mellitus (PTDM) is reversible in a considerable number of patients. We examined the prevalence and predictive factors of transient PTDM following liver transplantation. Forty-two of 74 PTDM patients showed the clinical features of transient PTDM. Compared with the persistent PTDM patients, they were characterized by younger age at the time of transplantation (49+/-7 vs. 53+/-8 yr, P<0.05), longer time before the development of PTDM (44+/-59 vs. 13+/-20 days, P<0.05), lower rate of hepatitis c virus seropositivity (0.0 vs. 9.4%, P<0.05), and use of mycophenolate mofetil (59.5 vs. 28.1%, P<0.05). Among these risk factors, age at the time of transplantation is the single independent predictive factor associated with the reversibility of PTDM.