The present disclosure provides a display substrate and a touch display device. The display substrate includes a base substrate and a functional film layer on the base substrate. The functional film layer is configured for reflecting light emitted from outside to the functional film layer. The display substrate further includes an encapsulation layer and a blocking layer; the blocking layer is on a side of the functional film layer facing away from the base substrate; the encapsulation layer is between the blocking layer and the functional film layer; an orthographic projection of the blocking layer onto the base substrate at least partially overlaps with an orthographic projection of the functional film layer onto the base substrate.