Abstract: A printed circuit board and a display device are provided. A second wiring layer of the PCB includes a trace group, a system ground and an output pin group that includes power supply pins and a reference ground pin. One end of the power trace of the trace group is connected to one power supply pin, and another end of the power trace extends toward the system ground line. The insulating layer has a via hole corresponding to an overlapping portion of the power trace and the positive power supply signal line. The reference ground trace is disposed between the two power traces. The reference ground trace is between the reference ground pin and the system ground line. Voltage on the reference ground pin is stable to provide a stable power supply voltage. The ripple of the power supply voltage is reduced. The electromagnetic interference resistance is strong.