BACKGROUND: The antitumor efficacy of immune checkpoint inhibitors (ICIs) has increasingly emerged during the last few years. However, there is a need to identify the safety profile of these agents more comprehensively, including liver toxicity. MATERIALS AND METHODS: Herein, we performed a meta-analysis to assess the risk of all-grade and grade 3-4 hypertransaminasemia in cancer patients receiving ICIs-as monotherapy or in combination with other anticancer agents. All the relevant trials were retrieved through EMBASE, Cochrane Library, and PubMed/Medline databases; eligible studies were selected according to PRISMA statement. The pooled relative risk (RR) and 95% confidence interval (CI) were extracted. RESULTS: Fifty-nine studies were included. The pooled RRs for all-grade AST and ALT increase were 1.45 (95% CI 1.26-1.67) (Supplementary Fig. 3) and 1.51 (95% CI 1.29-1.77) in patients receiving ICIs monotherapy and immune-based combinations compared to control treatment, respectively. The pooled RRs for grade 3-4 AST and ALT increase were 2.16 (95% CI 1.77-2.64) and 2.3 (95% CI 1.91-2.77). CONCLUSIONS: According to our results, ICIs monotherapy and immune-based combinations were associated with higher risk of all-grade and grade 3-4 hypertransaminasemia. Monitoring liver function should be recommended in cancer patients treated with ICIs monotherapy or immune-based combination, and in case of underlying liver disease, a careful risk-benefit assessment appears as a mandatory need.