An organic light emitting diode comprising: a first electrode in each of a first region, a second region and a third region; a first common layer on the first electrodes; a first red light emitting layer and a first green light emitting layer respectively in the first region and the second region; a first blue light emitting layer on the first red light emitting layer, the first green light emitting layer and the first common layer throughout the first to third regions; a charge generation layer on the first blue light emitting layer; a second common layer on the charge generation layer; a second red light emitting layer and a second green light emitting layer respectively on the second common layer in the first region and the second region; a second blue light emitting layer on the second red light emitting layer, the second green light emitting layer and the second common layer throughout the first to third regions; a third common layer on the second blue light emitting layer; and a second electrode on the third common layer; wherein the first, second and third common layers are each designated common layers since they are provided without disconnection throughout the first to third regions (SP1, SP2, SP3); and wherein the first and second red light emitting layers and the first and second green light emitting layers contact the lower surfaces of the first and second blue light emitting layers, characterized in that each of the first blue light emitting layer and the second blue light emitting layer comprises a first host related to excitation, a second host having an electron transporting property, and a blue dopant, and wherein the first blue light emitting layer directly contacts the charge generation layer and wherein a lowest unoccupied molecular orbital, LUMO, level of the second host is higher than a LUMO level of the first host by 0.2 eV to 0.5 eV a first electrode in each of a first region, a second region and a third region; a first common layer on the first electrodes; a first red light emitting layer and a first green light emitting layer respectively in the first region and the second region; a first blue light emitting layer on the first red light emitting layer, the first green light emitting layer and the first common layer throughout the first to third regions; a charge generation layer on the first blue light emitting layer; a second common layer on the charge generation layer; a second red light emitting layer and a second green light emitting layer respectively on the second common layer in the first region and the second region; a second blue light emitting layer on the second red light emitting layer, the second green light emitting layer and the second common layer throughout the first to third regions; a third common layer on the second blue light emitting layer; and a second electrode on the third common layer; wherein the first, second and third common layers are each designated common layers since they are provided without disconnection throughout the first to third regions (SP1, SP2, SP3); and wherein the first and second red light emitting layers and the first and second green light emitting layers contact the lower surfaces of the first and second blue light emitting layers, characterized in that each of the first blue light emitting layer and the second blue light emitting layer comprises a first host related to excitation, a second host having an electron transporting property, and a blue dopant, and wherein the first blue light emitting layer directly contacts the charge generation layer and wherein a lowest unoccupied molecular orbital, LUMO, level of the second host is higher than a LUMO level of the first host by 0.2 eV to 0.5 eV