An organic photoelectronic device includes an anode and a cathode facing each other, a light-absorption layer between the anode and the cathode, and a first auxiliary layer between the cathode and the light-absorption layer, the first auxiliary layer having an energy bandgap of about 3.0 eV to about 4.5 eV, and a difference between a work function of the cathode and a highest occupied molecular orbital (HOMO) energy level of the first auxiliary layer is about 1.5 eV to about 2.0 eV.