Abstract: As the first-line treatment for type 2 diabetes, metformin is widely used in clinical practice. Various transporters are associated with the absorption, distribution and excretion of metformin in vivo. Drugs concerning with these transporters may change pharmacokinetics and pharmacodynamics of metformin, leading to adverse drug interactions. The transporter-mediated drug-drug interactions were reviewed to provide a basis for rational application of metformin.