Type 2 diabetes mellitus （T2DM） is a heterogeneous disease with insulin deficiency and insulin resistance （IR） as the main etiology and is often accompanied by complications. Volatile oil is a volatile oily liquid extracted from natural plants， which has many pharmacological effects such as regulating Qi， relieving pain， inhibiting bacteria， and reducing inflammation. In recent years， there have been numerous reports on the treatment of T2DM by natural plant volatile oil and its effective components， which has become one of the new directions in the treatment of T2DM. With natural plant essential oil and its active components as the starting point， this paper comprehensively analyzed and summarized the material basis， mechanism， and signaling pathways of essential oil in the treatment of T2DM and its complications in China and abroad in recent years， and focused on the inhibitory effect of essential oil and its active components， such as carvacrol， paeonol， and β-caryophylene， on IR to improve T2DM by protecting pancreatic β-cells， inhibiting α-glucosidase activity， regulating the abundance and diversity of intestinal microbiota， and regulating glucose transporter protein type4 （GLUT4）， adenylate 5′-monophosphate-activated protein kinase （AMPK）， phosphatidylinositol-3 kinase （PI3K）/protein kinase B （Akt） signaling pathways to provide some references for the volatile oil intervention in T2DM and the development of new green antidiabetic drugs.