Display substrate, manufacturing method thereof and display device

The invention provides a display substrate (100), a manufacturing method thereof and a display device (200). The display substrate (100) comprises a substrate body (10) and a plurality of pixel units (PX), each pixel unit (PX) comprises a plurality of sub-pixels, and each sub-pixel comprises a light-emitting element and a pixel driving circuit; the functional layer (20) is positioned on one side of the substrate (10); the shading layer (30) is positioned on one side, far away from the substrate (10), of the functional layer (20), and the shading layer (30) is electrically connected with the functional layer (20); the buffer layer (34) is positioned on one side, far away from the substrate (10), of the shading layer (30) and covers the functional layer (20) and the shading layer (30); the active layer (40) is positioned on one side, far away from the substrate (10), of the buffer layer (34); the grid layer (50) is arranged on one side, far away from the substrate (10), of the active layer (40); a first via (60