Abstract: Arbuscular mycorrhizal fungi (AMF) can form symbiotic relationships with approximately 80% of terrestrial plants. Through their unique arbuscular structures within roots, they establish close contact with host cells to create a bidirectional nutrient exchange interface. This mutualistic mechanism not only enhances plant stress resistance but also reshapes ecosystem nutrient cycling. Like pathogenic fungi, the cell walls of AMF are primarily composed of chitin and β-glucans, which are key molecular patterns capable of triggering host plant immune responses. How AMF effectively evades host plant immunity remains unclear. Effector proteins secreted by pathogenic fungi have been found to play a crucial role in suppressing plant immune responses. During arbuscular mycorrhizal symbiosis, numerous effector proteins are also induced, which may similarly inhibit plant immunity and facilitate fungal colonization. This article reviewed and summarized current research on AMF effector proteins and discussed the future research directions and challenges. Studying effector proteins will help elucidate the regulatory mechanisms underlying the establishment and maintenance of AMF symbiosis, deepen our understanding of host-fungal interactions, and aid in selecting optimal fungal strains and plant varieties for enhanced symbiotic efficiency, thereby promoting sustainable agricultural development.