A display substrate and a display device are provided. The display substrate includes a first power signal line and a pixel defining layer. The first power signal line includes first power signal sub-lines extending along a first direction and second power signal sub-lines extending along a second direction. The pixel defining layer includes a plurality of openings to define effective light-emitting regions of a plurality of sub-pixels, the plurality of sub-pixels include a sub-pixel pair including two sub-pixels arranged along the second direction, and the sub-pixel pair includes two effective light-emitting sub-regions with an interval therebetween. In a plan view, the first power signal sub-line passes through the interval between the two effective light-emitting sub-regions, at least one second power signal sub-line includes a fracture, and the two effective light-emitting sub-regions are located at the fracture, so that a virtual straight line connecting two ends of a same fracture of the second power signal sub-line passes through the two effective light-emitting sub-regions. Providing the fracture in the second power signal sub-line can reduce the overlap between the two effective light-emitting sub-regions so as to reduce the color deviation of the sub-pixels.