Embodiments of the present application relate to an array substrate, the manufacturing method thereof and a display device. The array substrate comprises: a substrate, of gate lines and of data lines, a plurality of pixel units, defined by the gate lines and the data lines, each of the pixel units comprising a thin film transistor and a pixel electrode, wherein the thin film transistor comprises a source electrode, a drain electrode, an active layer, a gate insulating layer and a gate electrode, and the source electrode and the drain electrode are provided on the substrate opposing to each other with a channel of the thin film transistor provided therebetween, and the pixel electrode is positioned in a region outside the thin film transistor within the pixel unit, and is extended to a position above the drain electrode to be partly lapped over and directly connected to the drain electrode.