BACKGROUND & AIMS: Coronavirus disease 2019 (COVID-19) is a major global health threat. We aimed to describe the characteristics of liver function in patients with SARS-CoV-2 and chronic hepatitis B virus (HBV) co-infection. METHODS: We enrolled all adult patients with SARS-CoV-2 and chronic HBV co-infection admitted to Tongji Hospital from February 1 to February 29, 2020. Data of demographic, clinical characteristics, laboratory tests, treatments, and clinical outcomes were collected. The characteristics of liver function and its relation with the severity and prognosis of disease were described. RESULTS: Of 105 SARS-CoV-2 and chronic HBV co-infected patients, elevated levels of liver test were seen in several patients at admission, including elevated levels of alanine aminotransferase (22, 20.95%), aspartate aminotransferase (29, 27.62%), total bilirubin (7, 6.67%), gamma-glutamyl transferase (7, 6.67%), and alkaline phosphatase (1, 0.95%). The values of the indices mentioned above increased substantially during hospitalization (all P < .05). Fourteen (13.33%) patients developed liver injury. Most of them (10, 71.43%) recovered after 8 (range 6-21) days. Notably, 4 (28.57%) patients rapidly progressed to acute-on-chronic liver failure. The proportion of severe COVID-19 was higher in patients with liver injury (P = .042). Complications including ACLF, acute cardiac injury and shock happened more frequently in patients with liver injury (all P < .05). The mortality was higher in individuals with liver injury (28.57% vs 3.30%, P = .004). CONCLUSION: Liver injury in patients with SARS-CoV-2 and chronic HBV co-infection was associated with severity and poor prognosis of disease. During the treatment of COVID-19 in chronic HBV-infected patients, liver function should be taken seriously and evaluated frequently.