β-arrestin2, a pivotal protein within the arrestin family, is localized in the cytoplasm, plasma membrane and nucleus, and regulates G protein-coupled receptors (GPCRs) signaling. Recent evidence shows that β-arrestin2 plays a dual role in regulating GPCRs by mediating desensitization and internalization, and by acting as a scaffold for the internalization, kinase activation, and the modulation of various signaling pathways, including NF-κB, MAPK, and TGF-β pathways of non-GPCRs. Earlier studies have identified that β-arrestin2 is essential in regulating immune cell infiltration, inflammatory factor release, and inflammatory cell proliferation. Evidently, β-arrestin2 is integral to the pathological mechanisms of inflammatory immune diseases, such as inflammatory bowel disease, sepsis, asthma, rheumatoid arthritis, organ fibrosis, and tumors. Research on the modulation of β-arrestin2 offers a promising strategy for the development of pharmaceuticals targeting inflammatory immune diseases. This review meticulously describes the roles of β-arrestin2 in cells associated with inflammatory immune responses and explores its pathological relevance in various inflammatory immune diseases.