Obesity and the metabolic syndrome are major public health concerns, and present a formidable therapeutic challenge. Many patients remain recalcitrant to conventional lifestyle changes and medical therapies. Bariatric surgery has made laudable progress in the treatment of obesity and its related metabolic disorders, yet carries inherent risks. Unravelling the molecular mechanisms of metabolic disorders is essential in order to develop novel, valid therapeutic strategies. Mi(cro)RNAs play important regulatory roles in a variety of biological processes including adipocyte differentiation, metabolic integration, insulin resistance and appetite regulation. Investigation of these molecules and their genetic targets may potentially identify new pathways involved in complex metabolic disease processes, improving our understanding of metabolic disorders and influence future approaches to the treatment of obesity. This review discusses the role of miRNAs in obesity and related components of the metabolic syndrome, and highlights the potential of using miRNAs as novel biomarkers and therapeutic targets for these diseases.