Obesity is the major driver of the worldwide epidemic in type 2 diabetes (T2D). In the obese state, chronically elevated plasma free fatty acid levels contribute to peripheral insulin resistance, which can ultimately lead to the development of T2D. For this reason, drugs that are able to regulate lipolytic processes in adipocytes are predicted to have considerable therapeutic potential. G i-coupled P2Y 14 receptor (P2Y 14 R; endogenous agonist, UDP-glucose) is abundantly expressed in both mouse and human adipocytes. Because activated G i-type G proteins exert an antilipolytic effect, we explored the potential physiological relevance of adipocyte P2Y 14 Rs in regulating lipid and glucose homeostasis. Metabolic studies indicate that the lack of adipocyte P2Y 14 R enhanced lipolysis only in the fasting state, decreased body weight, and improved glucose tolerance and insulin sensitivity. Mechanistic studies suggested that adipocyte P2Y 14 R inhibits lipolysis by reducing lipolytic enzyme activity, including ATGL and HSL. In agreement with these findings, agonist treatment of control mice with a P2Y 14 R agonist decreased lipolysis, an effect that was sensitive to inhibition by a P2Y 14 R antagonist. In conclusion, we demonstrate that adipose P2Y 14 Rs were critical regulators of whole-body glucose and lipid homeostasis, suggesting that P2Y 14 R antagonists might be beneficial for the therapy of obesity and T2D.