Introducing high-index facets into nanocrystals (NCs) is an effective way for boosting the electrocatalytic intrinsic activity. However, the established NCs with high-index facets usually have a big diameter, which makes them exhibit a very limited surface area, thus finally limited mass activity. To embody the advantage of high-index facets in enhancing electrocatalysis well, the better nanostructures should meet the requirement of both high surface area and high-density high-index facets. Herein, we report our important advances in making the unique three-dimensional screw thread-like platinum–copper (Pt–Cu) alloy nanowires (NWs) with high-density high-index facets and controlled composition. Such special NWs with a high surface area of 46.90 m2 g–1 exhibit much better performance than the PtCu nanoparticles (NPs) in alcohol electrooxidations. This work opens a new way for maximizing the electrocatalytic performance by introducing high-index facets into high-surface-area stable bimetallic NWs.