Small molecules, which are called microRNAs (miRNAs) control the expression of genes negatively by reducing the levels of their targeted mRNAs they target. Recent research has demonstrated that miRNAs have a variety of functions in diabetes mellitus. The two main kinds of diabetes are type 1 diabetes (T1DM) and type 2 diabetes (T2DM). T2DM is brought on by dysfunctional islet β-cells in response to insulin resistance, whereas T1DM is characterized by a decrease in insulin release from the pancreatic β-cells may be due to auto-immune diseases and lead to absolute deficiency in insulin production. The miRNAs that regulate insulin synthesis and release are discussed in this review. This study covers the role of miRNAs as possible biomarkers for T2DM, as well as the prospective applications of miRNA-224 in diabetes