BACKGROUND: Infection is a major cause of morbidity and mortality following liver transplants. We evaluated the risk factors of mortality within 1 month of liver transplantation caused by post-transplant infections. METHODS: We retrospectively reviewed the medical records of 199 patients who underwent liver transplants from September 2005 to August 2010. We divided the enrolled patients into 3 groups. The first group, the Culture(-) group, was defined as those who had no significant culture results. The second group, the Culture(+)/survival group, was defined as those who tested positive for culture but survived longer than 1 month after transplantation. The third group, the Culture(+)/mortality group, was defined as those who died within 1 month of the transplant with positive culture test results. RESULTS: The culture(+)/mortality group consisted of more deceased donor liver transplants than other groups. Also, the Culture(+)/mortality group showed more evidence of pre-transplant infections, intensive care unit (ICU) admission, continuous post-transplant renal replacement therapy (CRRT), and a higher MELD score than other groups. The risk factors of early mortality combined with infection 1 month after liver transplantation are hospitalization in ICU before transplantation (HR=16.3, CI=2.6~102.3, P=0.003) and the positive results of culture within 7 days of the operation (HR=38.7, CI=4.1~368.8, P=0.001). CONCLUSIONS: Hospitalization in ICU before transplantation and an early positive culture result can be an early clinical indicator of a good prognosis after liver transplantation.