A display substrate and a display device are provided in the present invention. The display substrate includes a base substrate, and a positive power supply line, a negative power supply line and a first dam which are on the base substrate. The base substrate includes a display region and a peripheral region arranged around the display region. The positive power supply line, the negative power supply line and the first dam are in the peripheral region, and the first dam is arranged around the display region. At least in a corresponding region between the positive power supply line and the negative power supply line, a protruding structure is on a side of the first dam proximal to the display region.