microRNAs are a class of short non-coding RNAs containing about 19-22 nucleotides that regulate target gene expression through post-transcriptional repression or mRNA degradation, and involved in a variety of biological processes, such as cellular differentiation, proliferation, apoptosis and metabolism. microRNA-182 (miR-182), belonging to miR-183/96/182 cluster that consists of miR-182, -183, and -96, highly expresses in many cells and tissues, including osteoblasts, lymphocytes, adipocytes, retina, inner ear, etc. The recent studies of miR-182 highlighted its multiple important roles in differentiation, development, and functional maintenance in the cells and tissues. The dysregulation of miR-182 is associated with occurrence and development of many diseases, such as retinopathy, autoimmune diseases, cancers, obesity and diabetes. This review summarizes recent research progresses on the roles and mechanisms of miR-182 in cellular function and diseases.