Objective To investigate the clinical features of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant infection and abnormal liver function in Guangdong Province, China. Methods The patients with SARS-CoV-2 Delta variant infection who belonged to the same chain of transmission in Guangdong Province (Guangzhou and Foshan) and were admitted to Guangzhou Eighth People's Hospital, Guangzhou Medical University from May 21 to June 18, 2021 were enrolled in this study, and the judgment criteria for liver function were alanine aminotransferase (male/female) > 50/40 U/L, aspartate aminotransferase > 40 U/L, total bilirubin > 26 μmol/L, gamma-glutamyl transpeptidase > 60 U/L, and alkaline phosphatase (ALK) > 125 U/L. Abnormality in any one item of the above criteria was defined as abnormal liver function, and such patients were included in analysis (the patients, aged < 18 years, who had a mild or moderate increase in ALP alone were not included in analysis). Clinical data were compared between the patients with normal liver function and those with abnormal liver function, and the etiology and prognosis of abnormal liver function were analyzed. The Mann-Whitney U test was used for comparison of continuous data between two groups; the chi-square test was used for comparison of categorical data between two groups. Results Among the 166 patients with SARS-CoV-2 Delta variant infection, 32 (19.3%) had abnormal liver function with mild-to-moderate increases in liver function parameters, and compared with the normal liver function group, the abnormal liver function group had a significantly higher proportion of critical patients ( χ 2 =38.689, P < 0.001) and significantly higher age and inflammatory cytokines [C-reactive protein type, serum amyloid A, and interleukin-6 (IL-6)](all P < 0.05). Among the 32 patients with abnormal liver function, 13 patients had abnormal liver function on admission (defined as primary group), while 19 patients had normal liver function on admission but were found to have abnormal liver function by reexamination after treatment (defined as secondary group). For the primary group, the evidence of abnormal liver function was not found for 3 patients (3/13, 23.1%), and the possibility of toxic liver injury directly associated with SARS-CoV-2 infection was considered. Among the 19 patients in the secondary group, 9 (47.4%) had mild/common type and 10 (52.6%) had critical type, and all critical patients had the evidence of liver injury indirectly caused by the significant increases in C-reactive protein type, serum amyloid A, and IL-6 and hypoxemia; the evidence of abnormal liver function was not found for only 1 patient (1/19, 5.3%), and the possibility of toxic liver injury directly associated with SARS-CoV-2 infection was considered. All 32 patients with abnormal liver function had [JP2]significant reductions in liver function parameters after treatment including liver protection. Conclusion As for the patients with SARS-CoV-2 Delta variant infection who belong to the same chain of transmission in Guangdong Province, the critical patients show a significantly higher proportion of patients with abnormal liver function than the patients with other clinical types, and other factors except SARS-CoV-2 infection and indirect injury caused by SARS-CoV-2 infection are the main cause of liver injury.