Acinetobacter baumannii (AB), a highly pathogenic Gram-negative bacterium, exhibits remarkable environmental adaptability and prolonged survival. It can infect multiple sites in the human body and has become one of the most common pathogens in hospital-acquired infections due to its extensive acquired drug resistance, making the study of its pathogenic mechanisms urgent. Outer membrane proteins (OMPs) are among the key virulence factors of AB, contributing to adhesion and invasion, biofilm formation, immune evasion, and induction of apoptosis. In recent years, with the wide application of advanced technologies such as proteomics, transcriptomics and bioinformatics, significant progress has been obtained in the research on AB OMPs regarding structural biology, vaccine development and target identification, virulence mechanisms, and antimicrobial resistance. This review focuses on the pathogenic mechanisms of AB OMPs and the latest research advancements in this field.