Array substrate, manufacturing method thereof and display device

The embodiment of the invention provides an array substrate, a manufacturing method of the array substrate and a display device, and aims to cut off transmission of water vapor in a screen. The array substrate comprises a plurality of pixel areas, a first defining area and a second defining area. The first defining area surrounds each pixel area, and the second defining area surrounds at least one part of at least one pixel area. The array substrate comprises a first pixel light-emitting layer, a pixel definition layer, a first organic layer, a passivation layer and a second organic layer. The first organic layer is located in the second defining area and is located on one side of the pixel defining layer; the passivation layer is located in the second defining area and located on the side, away from the pixel defining layer, of the first organic layer or located between the first organic layer and the pixel defining layer; the second organic layer is arranged on one side, far away from the pixel definition layer, of the passivation layer and the first organic layer; the material of the second organic layer is the same as that of the first pixel light-emitting layer; the first organic layer is thicker than the second organic layer. The array substrate and the display device are used for realizing display.