Controlling aspect ratio of copper (Cu) nanowire (NW) is a vital role to determine the conductivity at a high transmittance for the transparent conductive electrode application, but systemic studies on aspect ratio control of Cu NW have been still in early stages. Herein, we systemically explore the aspect ratio of Cu NW by varying solution process parameters including reaction time and the concentration of additives (Cu precursor, reducing agent, and capping agent). From optimized process parameters, we successfully synthesize Cu NWs showing the high aspect ratio of ~ 1570, which is relatively comparable than that of previous reports. We characterize the sheet resistance with different transmittances, and consequently achieve excellent sheet resistance of 46 Ω sq−1 at transmittance = 93%, similar to that of indium tin oxide-based electrodes. Obtained Cu NW films also show stable bending reliability with applying bending radius of 6.5 mm. Such remarkable performances are attributed to high aspect ratio of our Cu NWs, which lead to reduced junction resistance in films.