A display substrate and a display device are disclosed, and the display substrate has a plurality of sub-pixels, and includes a base substrate, a driving circuit layer, a pixel definition layer and a light-emitting device layer, and a black matrix layer. Each sub-pixel includes a pixel driving circuit in the driving circuit layer and a light-emitting device in the light-emitting device layer. The black matrix layer includes a plurality of first light-transmitting openings respectively exposing the light-emitting devices of the plurality of sub-pixels in a direction perpendicular to a surface of the base substrate. The pixel definition layer includes a plurality of sub-pixel openings, at least part of the plurality of sub-pixel openings are in one-to-one correspondence with and at least partially overlapped with the plurality of first light-transmitting openings, and at least one of the plurality of first light-transmitting openings has an arc-shaped edge.