Abstract: Objective To investigate the clinical characteristics and influencing factors of liver dysfunction in patients with mental disorders, aiming to provide evidence for liver function monitoring and intervention in clinical practice. Methods Patients with mental disorders who were hospitalized at Beijing Anding Hospital from January 1, 2013, to December 31, 2023 were enrolled in this study. Demographic data, disease diagnoses, medication profiles, and liver function parameters-including alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and serum total bilirubin (TBIL)-were collected. The severity of liver dysfunction was graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 from the U.S. Department of Health and Human Services. Multivariate Logistic regression was used to analyze the factors associated with liver dysfunction. Results A total of 53 048 patients meeting the inclusion and exclusion criteria were enrolled. Among them, 49.8% had liver dysfunction, with elevated ALT being the most common abnormality (33.1%), followed by AST (25.4%), TBIL (17.3%), and ALP (4.3%). Most cases were mild (CTCAE grade 1). Logistic regression analysis indicated that male sex (OR=2.31, 95% CI:2.23-2.40), age 18-59 years (OR=1.79, 95% CI:1.69-1.89), mental disorders due to psychoactive substance use (OR=3.42, 95% CI:2.87-4.08), schizophrenia (OR=1.88, 95% CI:1.64-2.15), and use of antipsychotics (OR=1.38, 95% CI:1.30-1.47), mood stabilizers (OR=1.26, 95% CI:1.21-1.32), or sedative-hypnotics (OR=1.19, 95% CI:1.12-1.27) were associated with a higher risk of liver dysfunction (all P < 0.001). After treatment with hepatoprotective agents, 49.4% of patients achieved normalized liver function. Conclusion The incidence of liver dysfunction is high among hospitalized patients with mental disorders and is closely related to sex, age, diagnosis, and medication use. Enhanced liver function monitoring and timely intervention in high-risk populations are essential to improve patient outcomes.