Cardiovascular disease represents a major threat to human health with vascular atherosclerosis contributing significantly to its cause, particularly due to the ease of rupture of atherosclerotic plaques. The stability of atherosclerotic plaques is influenced by a variety of factors, including intraplaque neovascularization, the inflammatory response, smooth muscle cells and macrophages, and core lipid volumes. Thus, the investigation of factors affecting the stability of atherosclerotic plaques is of great significance for the development of new drugs for the treatment of atherosclerotic diseases. MicroRNAs are small single-stranded non-coding RNAs between 17 and 22 nucleotides in length. They are translated together with the untranslated region (UTR) of the target gene mRNA, where the completeness of base-pairing can influence the translation or degradation of the target genes. MicroRNAs can thus regulate gene expression at the post-transcriptional level and have been demonstrated to be extensively involved in the regulation of various factors affecting plaque stability. In this paper, we review microRNA development, factors affecting atherosclerotic plaque stability, and the relationship between microRNAs and plaque stability, with the aim of describing the mechanisms by which microRNAs affect gene and protein expression in relation to atherosclerosis progression (including plaque rupture) to suggest new therapeutic targets for atherosclerotic disease.