Thyroid hormone (TH) plays pivotal roles in metabolic homeostasis. The physiological function of TH is mainly mediated by thyroid hormone receptors (TRs). The role of TH in regulating metabolism has already led to several new therapeutic targets for metabolic disorders. Understanding the mechanisms of the various TH signalling pathways in metabolism will improve our likelihood of identifying novel therapeutic targets. In the past ten years, we profiled the miRNA expression in various metabolic tissues of mice under different thyroid states and identified multiple TH-regulated miRNAs, including miR-133a, miR-182, and miR-378 in skeletal muscle, and miR-378 in liver, respectively. Our recent data suggest that: 1) miR-133a mediates the effect of TH on muscle fiber type conversion and might contribute to the inhibitory effect of TH on myoblast proliferation; 2) miR-182 controls myofiber type determination and fuel selection in skeletal muscle, thereby modulating whole-body glucose homeostasis; 3) miR-378 plays a role in the metabolic regulation of cell death by targeting both autophagy and apoptosis in skeletal muscle; 4) hepatic miR-378 regulates glucose and lipid homeostasis by targeting a critical node in insulin signaling and mediates the TH action in cholesterol and energy metabolism. Based on our studies, we propose that TH is able to achieve its regulatory effect on metabolism through miRNA-mediated mechanisms.