Background: Liver transplantation (LT) is the only curative therapy for acute and chronic end-stage liver disease in pediatrics. Nevertheless, bacterial infection post-transplant account for one of the most significant causes of mortality which requires attention, along with appropriate antibacterial treatment. Therefor this study was designed to provide a multifaceted overview of bacterial infections during a one-year experience in the biggest pediatrics LT center in Iran.Methods: In this retrospective cohort study, records from all liver transplant pediatrics in Abu-Ali Sina hospital, Shiraz, Fars, Iran from April 2019 to February 2020 were assessed. Demographic, laboratory, and clinical data were extracted along with the administered therapeutic approach for the patient.Results: an incidence of 67.9% bacterial infection rate was observed, in which more than 64.06% of isolated pathogens were Gram-negative and 35.93% were gram-positive. The most isolated pathogens were E. coli sp. and pseudomonas sp. for gram negative, and enterococci and staph sp. for gram positive. Our study demonstrated that Intra-abdominal Surgical Site Infections (24.24%) was the most common site of infections in post LT pediatrics. According to the results of the sensitivity-resistance pattern of isolated pathogens, 24.39% of isolated gram-negative bacteria were Extensively drug resistant (XDR). Also, 30.43% of gram-positive bacteria were Vancomycin-resistant enterococci (VRE) and 8.69% of them were methicillin-resistant staphylococcus aureus (MRSA). Furthermore, multivariate regression analysis showed that the only risk factor for bacterial infections after LT is the length of stay in the ICU. The mortality rate in our study was 22%, which was significantly higher among the infection group (P = 0.008). Also, it was found that patients receiving colistin had a significantly shorter in length of stay in the ICU and hospital than those who did not receive colistin. There is no any significant difference between piperacillin-tazobactm versus meropenem as empirical treatment regarding clinical outcomes.Conclusion: a high rate of bacterial infection was detected among hospitalized pediatrics in the early period after LT. High antibacterial resistance of bacteria isolated from LT pediatrics is alarming. Furthermore, Replacement of piperacillin-tazobactam instead of carbapenems in empirical treatment should be considered.