Background and Aims There is an urgency to find new treatments for type 2 diabetes mellitus (DM2), a devastating disease worldwide. Insulin resistance is a major hallmark of DM2. This is why current pharmacological therapies to treat DM2 are focused countering insulin resistance. In this work, we aimed to investigate the potential therapeutic use of Leptolide (a member of furanocembranolide’s family) to enhance insulin sensitivity in HepG2 cells and in diet-induced obese mice. Material and Methods Six weeks old C57BL/6J male mice were fed regular diet (SD) or high fat-diet (HFD; 60% kcal fat) for 6 weeks. Afterwards, they were treated with daily i.p. injections of Leptolide (100µg/kg) or vehicle for one month receiving the same kind of diet (SD/HFD). Intraperitoneal glucose tolerance and insulin sensitivity were assessed at the end of the treatment. Plasma insulin, triglycerides (TG) and cholesterol (CHL) were measured after treatment. Insulin signaling (p-PKB/PKB) was measured in liver of HFD+/- Leptolide mice. Insulin resistance was activated in HepG2 cells using 0.2mM palmitate and insulin signaling was studied 24h after 0.1μM Leptolide treatment. Results Diet-induced obese mice exhibited improved glucose tolerance and insulin sensitivity. Livers of HFD-mice showed enhanced ~2-fold PKB phosphorylation after insulin injection when treated with Leptolide. In parallel, HFD treated with Leptolide showed ~30% reduced plasma insulin levels and ~12% reduced plasma TG levels. Importantly, these beneficial effects on glucose homeostasis, lipid levels and insulin sensitivity were not accompanied by toxicity. These results nicely correlate with those obtained in insulin resistant HepG2 cells, where Leptolide increased insulin signaling (p-PKB/PKB) by 2-fold. Conclusion We have identified Leptolide as a new potential treatment for insulin resistance and DM2.