BACKGROUND Although acute kidney injury (AKI) is regarded as a frequent complication following deceased donor liver transplantation, the incidence of AKI following living donor partial liver transplantation (LDLT) has not yet been sufficiently investigated. METHODS we used two definitions and investigated the influence of AKI on patient and graft survival. The definitions for the degree of AKI were as follows: AKI 1 was characterized by an increase in serum creatinine of 0.5 mg/dL, while AKI 2 was 1.0 mg/dL above the baseline within one wk during the post-operative course. The incidence and its impact were investigated. RESULTS The incidence of AKI 1 was 63.1%. The development of AKI 1 was correlated with intra-operative blood loss (p = 0.013), the length of post-operative ICU stay, and hospitalization (p = 0.020 and 0.038). The incidence of AKI 2 was 27.7%, and AKI 2 was correlated with the length of both the post-operative ICU and hospital stays. The development of AKI 2 was significantly correlated with graft survival (p = 0.015). CONCLUSIONS Recognizing the peri-operative risk and development of AKI is important, because AKI post-LDLT is associated with a poorer graft survival and a possible worse long-term prognosis.