An array substrate and a fabrication method thereof and a display device are provided. The array substrate comprises: a base substrate; a plurality of gate lines and a plurality of data lines formed on the base substrate, the plurality of gate lines and the plurality of data lines intersecting with each other to define a plurality of sub-pixels, each of the sub-pixels including a thin film transistor and a pixel electrode, and the plurality of sub-pixels including a first sub-pixel; a passivation layer formed on the base substrate and covering the gate lines, the data lines and the thin film transistor, a via hole being provided in the passivation layer and the pixel electrode being formed on the passivation layer and connected with a drain electrode or a source electrode of the thin film transistor through the via hole in each of the sub-pixels; and a first spacer, provided in the via hole of the first sub-pixel.