Provided are a display substrate, a testing method therefor and a preparation method therefor, and a display panel, which are used for improving the success rate of transistor testing. The display substrate comprises a base substrate and a pixel circuit, wherein the pixel circuit comprises an active layer, a first gate insulating layer, a first gate electrode layer, a second gate insulating layer, a second gate electrode layer, a first interlayer insulating layer, a source/drain electrode layer, and a second interlayer insulating layer. The pixel circuit is divided into a plurality of transistors, and further comprises a gate electrode contact hole and a source/drain electrode contact hole. The source/drain electrode layer comprises a gate electrode test pad which is electrically connected to the first gate electrode layer by means of the gate electrode contact hole, and a source electrode and a drain electrode which are electrically connected to the active layer by means of the source/drain electrode contact hole. The second interlayer insulating layer is provided with a gate electrode test hole and a source/drain electrode test hole, wherein the gate electrode test hole exposes the gate electrode test pad, and the source/drain electrode test hole exposes part of an area in the source/drain electrode layer other than the gate electrode test pad.