Abstract Au/Ir bimetals are not easy to obtain because alloy phase diagrams are not available for these material combinations (Ronald et al., 2004). Herein, the Au/Ir nanochains (Au/Ir NCs) are synthesized via one-pot, hydrothermal method. By virtue of jagged surface with abundant atomic defects, the Au/Ir NCs are demonstrated much more active than commercial IrO2 electrocatalysts for oxygen evolution reaction under alkaline media. The potential of the Au/Ir NCs sustains 1.53 V vs reversible hydrogen electrode (RHE) with no obvious decease under current density at 10 milliamps per square centimeter, while that of IrO2 increase to 1.65 V vs RHE after stability tests for ca. 32 h. The durability as well as the activity of Au/Ir NCs is attributed to the electronic interaction between Au and Ir, which is confirmed by X-ray photoelectron spectroscopy (XPS).