The invention relates to an electronic load, which comprises a loading module (1), the loading module (1) comprises a transistor (8) and an adjusting circuit (9), and the adjusting circuit is used for adjusting the on-resistance of the transistor. The invention is characterized in that the electronic load also comprises a switching device (4), a direct current power supply (2) and two sub-circuits, the direct current power supply (2) is connected with one of the two sub-circuits in series, and the switching device (4) is used for ensuring the load module (1) to be connected with one of the two sub-circuits. The invention overcomes the faults that in the prior electronic load, when the voltage of the two ends of the fuel battery is smaller than a certain value, super small on-resistance can not be realized, and the resistance capacity can not be adjusted. The electronic load provided by the invention is adopted by the system and method of evaluating the discharging performance of the fuel battery provided by the invention, the performance is stable, and the adaptability is strong.