<p>Bitter taste receptors belong to the class A of the GPCR superfamily of G protein-coupled receptors. Bitter taste receptors have different numbers and structures in different species, and an analysis of their structures facilitates the discovery and development of their agonists and inhibitors. In addition, bitter taste receptors differ in expression between species and tissues, which corresponds to the diversity and specificity of their mechanisms of action. At present, bitter taste receptors also have a wide range of effects on the treatment of diseases, including gastrointestinal, airway, heart, orthopedic, urinary disease, and cancer. Therefore, this article reviewed the structure, expression, function, and mechanism of bitter taste receptors, in order to develop more bitter taste receptors and bitter ligands for treatment, and provide some new ideas and goals for the clinical use of bitter drugs.</p>