Fragile X syndrome(FXS) is the most common inherited cognitive disorder, and is also a kind of severe gene diseases associating with autism spectrum disorders (ASDs). It is principally caused by the abnormal amplification of fragile X mental retardation gene 1 (FMR1) and abnormal methylation of CpG island on its upstream, then leading to the reduction or deficiency of its protein product fragile X mental retardation protein (FMRP). Both FMRP and miRNA have transcriptional repression activity, and FMRP was related to miRNA regulation pathway in the biochemical and genetic. In addition, more and more studies showed that miRNA regulation pathway plays a role in the synthesis and translation regulation of miRNA. In this review, the role of miRNA in the pathogenesis and treatment of FXS. Thus in this paper, we described the functions of miRNA and its interaction with the fragile X protein family members, laying the foundation for understanding the nosogenesis of FXS at the level of miRNA.