A light-emitting device (100, 200) comprising: a plurality of first electrodes (110, 210) respectively in a first sub-pixel, a second sub-pixel, and a third sub-pixel; a second electrode (150, 250) facing the plurality of first electrodes (110, 210); a first emission layer (130a, 230a) in the first sub-pixel and configured to emit a first color light; a second emission layer (130b, 230b) in the second sub-pixel and configured to emit a second color light, wherein the second emission layer (130b, 230b) includes a host and a light emitting dopant; a first layer (130c, 230c) positioned between the first electrode and the first emission layer that is integrated with the first sub-pixel, the second sub-pixel, and the third sub-pixel, wherein the first layer (130c, 230c) includes a host and a light emitting dopant; a first auxiliary layer (130', 230') between the first layer (130c, 230c) and the first emission layer (130a, 230a), wherein the first auxiliary layer (130', 230') is confined to the first sub-pixel; and a first intermediate layer (131, 231) between the first auxiliary layer (130', 230') and the first emission layer (130a, 230a), wherein an absolute value of a highest occupied molecular orbital (HOMO) energy level of the first intermediate layer (131, 231) is larger than an absolute value of a HOMO energy level of the first auxiliary layer (130', 230') and smaller than an absolute value of a HOMO energy level of the first emission layer (130a, 230a), an absolute value of a lowest unoccupied molecular orbital (LUMO) energy level of the first intermediate layer (131, 231) is larger than an absolute value of a LUMO energy level of the first auxiliary layer (130', 230') and smaller than an absolute value of a LUMO energy level of the first emission layer (130a, 230a), the first emission layer (130a, 230a) comprises a first host and a first dopant, and the first dopant is configured to emit light having a full width at half maximum (FWHM) of about 35 nm or more, wherein: the first electrode (110, 210) is an anode, the second electrode (150, 250) is a cathode, a region in the first layer (130c, 230c) corresponding to the third sub-pixel is configured to emit a third color light, and a resonance order of one selected from the first color light, the second color light, and the third color light is different from resonance orders of the other two thereof. a plurality of first electrodes (110, 210) respectively in a first sub-pixel, a second sub-pixel, and a third sub-pixel; a second electrode (150, 250) facing the plurality of first electrodes (110, 210); a first emission layer (130a, 230a) in the first sub-pixel and configured to emit a first color light; a second emission layer (130b, 230b) in the second sub-pixel and configured to emit a second color light, wherein the second emission layer (130b, 230b) includes a host and a light emitting dopant; a first layer (130c, 230c) positioned between the first electrode and the first emission layer that is integrated with the first sub-pixel, the second sub-pixel, and the third sub-pixel, wherein the first layer (130c, 230c) includes a host and a light emitting dopant; a first auxiliary layer (130', 230') between the first layer (130c, 230c) and the first emission layer (130a, 230a), wherein the first auxiliary layer (130', 230') is confined to the first sub-pixel; and a first intermediate layer (131, 231) between the first auxiliary layer (130', 230') and the first emission layer (130a, 230a), wherein an absolute value of a highest occupied molecular orbital (HOMO) energy level of the first intermediate layer (131, 231) is larger than an absolute value of a HOMO energy level of the first auxiliary layer (130', 230') and smaller than an absolute value of a HOMO energy level of the first emission layer (130a, 230a), an absolute value of a lowest unoccupied molecular orbital (LUMO) energy level of the first intermediate layer (131, 231) is larger than an absolute value of a LUMO energy level of the first auxiliary layer (130', 230') and smaller than an absolute value of a LUMO energy level of the first emission layer (130a, 230a), the first emission layer (130a, 230a) comprises a first host and a first dopant, and the first dopant is configured to emit light having a full width at half maximum (FWHM) of about 35 nm or more, wherein: the first electrode (110, 210) is an anode, the second electrode (150, 250) is a cathode, a region in the first layer (130c, 230c) corresponding to the third sub-pixel is configured to emit a third color light, and a resonance order of one selected from the first color light, the second color light, and the third color light is different from resonance orders of the other two thereof. the first electrode (110, 210) is an anode, the second electrode (150, 250) is a cathode, a region in the first layer (130c, 230c) corresponding to the third sub-pixel is configured to emit a third color light, and a resonance order of one selected from the first color light, the second color light, and the third color light is different from resonance orders of the other two thereof.