A LED sensing system and a display panel sensing system are disclosed. The LED sensing system comprises LEDs and a driver. The LEDs are arranged in a LED array, and the driver is disposed on a central portion of the LED array and electrically connected to the LEDs respectively. The driver can receive an activation maintenance signal, and receive an input address, and turn on one of the LEDs corresponding to the input address, so as to obtain a magnitude of a voltage of the LED corresponding to the input address for determining performance of the LED and a yield rate of the LED array.