Objective: Leukocyte cell-derived chemotaxin 2 (LECT2) is a recently discovered hepatokine that mediates obesity-related metabolic disturbances. Dipeptidyl peptidase-4 (DPP-4) inhibitor has received much attention as a novel therapeutic agent for inflammatory disorders, including non-alcoholic fatty liver disease (NAFLD). However, there has been no research examining the function of LECT2 or a novel DPP-4 inhibitor, gemigliptin, in the pathogenesis of NAFLD and their underlying connections Methods: In HepG2 cell line, the signaling of LECT2 and gemigliptin were analyzed by Western blotting. C57BL/6 mice were used to confirm the role of gemigliptin on liver disorder and LECT2 expression. Results: LECT2 increased mammalian target of rapamycin (mTOR) phosphorylation, sterol regulatory element-binding protein (SREBP)-1 cleavage, lipid accumulation, and insulin resistance in the HepG2 cells. Gemigliptin increased AMP-activated protein kinase (AMPK) phosphorylation and inhibited tumor necrosis factors (TNF) α-induced mTOR phosphorylation, SREBP-1 cleavage, lipid accumulation, and LECT2 expression in HepG2 cells. Furthermore, gemigliptin recovered TNFα-induced insulin resistance, which was abolished in LECT2 knockdown cells. All these gemigliptin-induced protective effects were attenuated by an AMPK inhibitor in the HepG2 cells. In an in vivo study, HFD-plus-gemigliptin-fed mice showed improvement in hepatic steatosis and insulin resistance compared with HFD-fed mice. In preliminary in vivo experiments, gemigliptin induced AMPK phosphorylation and inhibited LECT2 expression in liver tissues. Conclusion: Gemigliptin may alleviate hepatic steatosis and insulin resistance through the inhibition of LECT2 expression via AMPK dependent mechanisms, suggesting its direct protective role in the progression of NAFLD.