This study is to propose a QD-LED device that can control the distribution of electrons and holes through the doping of other materials on the QD and modulate the color by the applied voltage of the device. In this study, the presented QD-LED device was coated with EML emitting different colors on the same device and doped with PCBM to control the holes distributed in the green QD. Three characteristics that vary depending on the concentration of PCBM doping were analyzed, and a color-tunable device capable of controlling the emission color and color range was fabricated.