Objective：Exosomes as vesicles are secreted by a variety of cells in the human body，they exist in serum，urine，saliva and follicular fluid. These molecules play important regulatory roles in many biological and pathological processes，such as cell differentiation，proliferation/growth，apoptosis，angiogenesis and inflammation. The microRNA（miRNA）is a small noncoding RNA，about 17-24 nt，it mediates posttranscriptional regulation by binding to complementary sequences on messenger ribonucleic acid（mRNA）and promoting mRNA degradation or translation inhibition. miRNA is closely related to the occurrence and development of polycystic ovary syndrome，abortion，endometriosis and ovarian cancer. Therefore，exosomal miRNA has a wide range of clinical application potential in the monitor and treatment of disease.