1. A display substrate, which includes an anode layer, a cathode layer and a luminous layer that is provided between the anode layer and the cathode layer, the anode layer including a plurality of anodes and the luminous layer including a plurality of luminous regions, wherein the display substrate further includes at least one assisting electrode, the at least one assisting electrode being insulated and spaced from the anodes, and the at least one assisting electrode contacting the cathode layer in parallel, such that a total resistance of the at least one assisting electrode and the cathode layer connected in parallel is smaller than a resistance of the cathode layer alone, wherein the at least one assisting electrode and the anode layer are provided in a same layer, and the display substrate further includes a spacer, insulation gaps are respectively formed at two sides of the at least one assisting electrode, a portion of the spacer being provided within the corresponding insulation gap and another portion of the spacer protruding from the anode layer, so as to space and insulate the at least one assisting electrode and the plurality of anodes, wherein there are a plurality of pairs of spacers, and the plurality of pairs of spacers divide the display substrate into a plurality of anode regions and a plurality of assisting electrode regions, each of the anode regions being provided therein with at least one anode and luminous region, each of the assisting electrode regions being provided therein with at least one of the assisting electrodes, the assisting electrode region being provided around the anode regions, a width of the assisting electrode regions being smaller than a width of the anode regions, a portion of the cathode layer being located within gap between a pair of the spacers in the assisting electrode regions so as to electrically connect the cathode layer and the assisting electrodes, and wherein shapes of the luminous regions formed in two anode regions at two sides of the assisting electrode are different.