Irritable bowel syndrome ( IBS) is a common functional gastrointestinal disorder. The lack of early diagnostic method and effective pharmacotherapy of IBS is predominantly attributed to the current limited understanding of its pathogenesis. MicroRNA (miRNA) is a class of small noncoding RNA of approximately 22 nt in length, which regulate gene expression by post-transcriptional repression or degradation of mRNAs, most often leading to gene silencing. Studies have revealed various differentially expressed miRNAs in colon tissue and peripheral blood of IBS patients. MiRNA has varying degrees of influence on the intestinal flora of IBS patients, the intestinal mucosal barrier, and low grade intestinal inflammation. This review focuses on miRNAs in IBS to find evidence of miRNA involvement in IBS pathogenesis and verify the diagnostic and therapeutic value of miRNA in IBS.