Infections represent the most significant complication after liver transplantation and significantly increase the morbidity and mortality of the patient. Numerous risk factors affect the development and frequency of infections, the most important being long-term immunosuppression, infectious and other diseases of recipients and donors, and the surgical procedure itself. Regarding the time of infection, they are divided into infections of early, intermediate and late posttransplantation period. The causal agents are related to the specific period. In the early period the most frequent are bacterial nosocomial infections, with a high frequency of multi-resistant bacteria. After that period the incidence of nosocomial infections decrease and a growing number of opportunistic infections is noted, with viruses as the main causal agents and the reactivation of latent infections as well. In the late period, outbreaks of infection may occur, and the etiology depends on the epidemiological setting of the environment in which the recipient resides. Infections may interfere with any organic system. The clinical presentation is individual and the symptoms are often hidden due to the immunosuppressed state of the patient. The strength of the infectious events varies from mild, self-limiting inflammation to severe infection with septic complications and organ failure. Combating infections involves proper use of immunosuppressive therapy after transplantation, proper selection and dosing of antimicrobial drugs and high quality of prevention and prophylactic measures. The aim of this review is to present the current knowledge on infections after liver transplantation, to associate the occurrence of infections with risk factors and to demonstrate the most important causes and ways of preventing infectious events.