Abstract
(1) Background: This article reviews the biological characteristics of phenolic acid compounds, focusing on their mechanisms of action in various liver diseases. (2) Methods: The review adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We utilized PubMed and Web of Science databases to search for relevant studies on the use of phenolic acids in liver diseases from 2015 to 2025. (3) Results: Phenolic acids can improve different types of liver diseases, including drug-induced liver injury (DILI), alcoholic liver disease (ALD), metabolic dysfunction-associated steatotic liver disease, liver fibrosis, and liver cancer. Their beneficial effects are attributed to mechanisms such as anti-inflammatory properties, antioxidant activity, regulation of lipid metabolism, inhibition of cell apoptosis, and modulation of gut microbiota. (4) Conclusion: Phenolic acids exhibit a good protective effect against various liver diseases and are associated with multiple signaling pathways. However, the primary target cells and specific molecular targets of phenolic acids remain unclear, necessitating further research to elucidate their protective mechanisms in liver diseases.