In 2004, we implemented a referral system for patients with acute liver injury (ALI) based on an established formula that estimates the risk of progression to acute live failure (ALF); however, the benefits of the system for patients with severe acute liver injury (SLI) remain unclear. We have evaluated the clinical significance of the referral system for SLI patients. Patients with ALI/SLI who were consecutively and prospectively listed on the system between 2004 and 2018 were analyzed. Of the 371 ALI/SLI/ALF patients on the system, 124 satisfied the criteria for SLI; 34 of these 124 progressed to SLI after registration. Multivariate analysis using age, sex, AST, ALT, creatinine, total bilirubin, prothrombin, presence of hepatic encephalopathy (HE), and SLI at registration revealed that HE was associated with high mortality. Among the 23 patients who developed HE, five who progressed to SLI after registration showed an increased time to HE development compared with patients who had SLI at the time of registration. However, there was no significant difference in survival time after HE development. We concluded that early identification of SLI patients using the referral system increased the time from SLI diagnosis to HE development.