The CFEM （common in fungi extracellular membrane） protein is an extracellular membrane protein that is unique to fungi and often founctions as an effector in various fungal species. This article elucidates the structure， origin， evolution， function， and molecular mechanisms of CFEM proteins across different pathogenic fungi. It highlights the critical roles of CFEM proteins in pathogenic fungi， including iron acquisition， maintenance of fungal cell wall integrity， influence on fungal growth and development， facilitation of infection structure formation， and elicitation of host immune responses. Additionally， a bioinformatic analysis of CFEM proteins in Penicillium expansum is presented. Future research directions on the roles and molecular mechanisms of CFEM proteins in fungal pathogenicity are also discussed. The aim is to enhance our understanding of the function and molecular mechanisms of CFEM proteins in fungal infection and pathogenesis， providing a theoretical foundation and reference for controlling plant fungal diseases.