Free fatty acids (FFAs) present in our dietary fats not only act as vital nutrients but also function as signalling molecules and modulate key biological functions through their active involvement in a multitude of energy metabolism pathways. However, it has been reported that excessive intake of dietary fat contributes to the development of different types of Diabetes mellitus. Free fatty acid receptors are the key regulators of the most metabolic disorders. Among them, diabetes mellitus is a severe growing disorder and found in every corner of the world. Various metabolic disorders, particularly for type 2 diabetes mellitus, these different free fatty acid receptors are being explored as drug targets. In the present review, it has been explored various FFAs sensing G-protein coupled receptors (GPR) likes GPR40 (FFAR1), GPR43 (FFAR2), GPR41 (FFAR3), GPR120 (FFAR4), and GPR84 as emerging novel therapeutic targets for antidiabetic drugs. Additionally, this review has covered pre-clinical discovery and development of different selective ligands targeted to these receptors starting from hit identification to lead optimization via chemical modification and the challenges and tactics selected by different medicinal chemists to improve potency, physicochemical properties, safety profiles, and pharmacokinetics of different FFAR agonists for making a potential drug candidate. Several molecules have been withdrawn in the clinical trials without reporting any reasons. We believe that this review will help the researchers to find a new direction in the discovery of new antidiabetic drugs.