Electrochemical reduction of CO2 to various chemicals is a promising approach to dealing with excessive CO2 accumulation in the atmosphere. Even though numerous electrocatalysts have been extensively utilized for the reaction, several challenges remain such as high overpotential, poor stability, and low selectivity followed by the domination of hydrogen formation. To overcome these problems, multi-component materials have been proposed due to their advanced catalytic activity compared to single-component materials. Herein, we present preparation of the indium-doped tin oxide nanowires (In-SnO2 NWs) as an efficient electrocatalyst to promote CO2 reduction into formate. The unique 1D structure of SnO2 NWs with simultaneously doped-In (5.4at% In) can enhance the selectivity toward formate by up to ∼82 % compared to bare SnO2 NWs (∼58.9 %) at −1.04 V (vs RHE). The modified SnO2 surface driven by In-doping induces electron delocalization in between, and the surface defects provide more active sites. Thus, the intermediate could be stably adsorbed to produce more formate ions.