a base substrate, comprising a first display region, a second display region and a third display region, wherein the first display region comprises a plurality of first light emitting unit groups and a plurality of first pixel circuit groups respectively connected with the plurality of first light emitting unit groups, the second display region comprises a plurality of second light emitting unit groups, a plurality of second pixel circuit groups and a plurality of third pixel circuit groups, the plurality of second light emitting unit groups are respectively connected with the plurality of second pixel circuit groups, the third display region comprises a plurality of third light emitting unit groups, which are respectively connected with the plurality of third pixel circuit groups, and a density of the plurality of second light emitting unit groups and a density of the plurality of third light emitting unit groups are both smaller than a density of the plurality of first light emitting unit groups, each light emitting unit group comprises a plurality of light emitting units, and each of the light emitting units comprises a first electrode, a light emitting layer, and a second electrode which are sequentially arranged along a direction perpendicular to the base substrate, and the second electrode is on a side of the light emitting layer facing the base substrate,

wherein the second electrode of each of the light emitting units comprises a main body electrode and a connection electrode, the connection electrode is configured to connect a pixel circuit, and each light emitting unit group located in display regions comprises a plurality of light emitting units of different colors;

among the light emitting units of a same color, an area of the main body electrode of at least one light emitting unit located in the third display region is greater than an area of at least one main body electrode located in the first display region.