A tandem organic light-emitting diode, an array substrate and a display device are provided. The tandem organic light-emitting diode includes an anode, a hole transport layer, a first light-emitting layer, a first charge generation layer, a second charge generation layer, a third charge generation layer, a fourth charge generation layer, a second light-emitting layer, an electron transport layer and a cathode which are sequentially laminated, wherein the first charge generation layer is an N-type bulk heterojunction, the second charge generation layer and the third charge generation layer are both PN junction type bulk heterojunctions, a proportion of the P-type organic material in the second charge generation layer is greater than that of the N-type organic material, a proportion of the P-type organic material in the third charge generation layer is less than that of the N-type organic material, and the fourth charge generation layer is a P-type bulk heterojunction.