MicroRNA (miRNAs) is a class of non-coding RNA with a length of 22-25 nt. They can bind to the 3'-untranslated region (3'-UTR) of target mRNAs in the form of complete or incomplete base complementary pairing, causing the degradation or translation inhibition of target mRNAs. Follicles are the functional unit of the ovary. Multiple miRNAs can be detected in different stages of follicular development, and the expression of these microRNAs has a certain temporal and spatial specificity. Recent studies have shown that miRNAs are involved in various stages of follicular development, such as primordial follicle recruitment, dominant follicle selection, granulosa cell proliferation and differentiation, steroid hormone synthesis and secretion, oocyte maturation, ovulation and luteal formation. In addition, abnormal expression of miRNAs are closely related to the occurrence and development of diseases such as premature ovarian failure and polycystic ovarian syndrome. To further explore the regulatory role of miRNAs in follicular development will provide ideas for further understanding of ovarian follicular development and the diagnosis and treatment of female-related diseases.

MicroRNA; Follicular development; Granulosa cells; Ovarian dysfunction