Abstract: Endoplasmic reticulum stress refers to a cellular stress response triggered when cells are stimulated, which is manifested as the disruption of endoplasmic reticulum homeostasis and dysfunction in various pathological conditions, resulting in the accumulation of a large number of misfolded and unfolded proteins within the endoplasmic reticulum and an imbalance of calcium ions. Macrophages are the most abundant immune cells in the liver and play an important role in maintaining liver homeostasis and various liver diseases. Recent studies have confirmed that the unfolded protein response caused by endoplasmic reticulum stress plays an important role in regulating macrophage immune response. This article reviews the mechanisms of endoplasmic reticulum stress regulating macrophage immune response and its role in liver diseases such as ischemia-reperfusion injury during organ transplantation, liver fibrosis, and hepatocellular carcinoma, in order to deepen the understanding of the mechanism of macrophage immune regulation and provide new ideas for research and interventional treatment related to liver diseases.