Abstract: Some electrochemical tests were taken to analyze the electrode activating process of C/KOH/Ni（OH）<SUB<2</SUB< hybrid capacitor. The results proved that, the activation of activated carbon electrode, which was an electrode process of electric double-layer capacitor, would be carried out quickly. And the electrode capability would be stable after 30 cycles. The activation of Ni（OH）<SUB<2</SUB< electrode was the key factor to decide the performance of hybrid capacitor. Ni<sup<3+</sup< would be accumulated in Ni（OH）<SUB<2</SUB< electrode, the constitution of the surface of activated material would be changed under the coaction of additives in the activating process. The OER （oxygen evolution reaction） potential of the electrode would be raised, the electric conduction, capacity and fast charge-discharge performance of the electrode would be improved.