A pixel compensation circuit is provided. The pixel compensation circuit includes a detecting circuit, a repairing circuit, a compensating circuit, and a light-emitting device. The detecting circuit is electrically coupled with the repairing circuit, the compensating circuit, and the light-emitting device. The compensating circuit is configured to provide a fixed current to the light-emitting device. The detecting circuit is configured to detect a current flowing through the light-emitting device. The repairing circuit is configured to determine a compensation current according to the current detected by the detecting circuit and input the compensation current into the light-emitting device. A display substrate and a display device are further provided.