The present application discloses a display panel driving circuit and a display panel. The display panel driving circuit includes a driving circuit and a light-emitting diode. The driving circuit is connected to the light-emitting diode. The driving circuit includes a plurality of superimposed driving modules, and a corresponding number of driving modules are selectively conducted according to a preset grayscale. Each driving module includes a scan control transistor, a switch transistor and a drive transistor, in each driving module the scan control transistor is connected to the drive transistor via the switch transistor, in each driving module a first end of the scan control transistor is connected to a scan signal terminal, and the light-emitting diode and the drive transistors of the driving modules are sequentially connected. The present application can better increase the number of grayscales, thereby improving image quality.