Abstract: MicroRNAs (miRNAs) are a class of small non-coding RNA with regulatory functions, which are related to the occurrence of many human diseases. MiRNAs are stable and can be detected by repeated sampling, and they are considered as one of the most promising tumor markers.Research has confirmed the role of miRNAs in the development, invasion and metastasis, diagnosis as well as treatment and prognostic detection of breast cancer.This paper reviewed the research progress in this field in recent years.