Activated carbon serving as electrode materials for supercapacitors were prepared by a polymer blend carbonization and steam activation method using phenol formaldehyde resin (PF)as carbon precursor and polyethylene glycol（PEG）as pore-forming agent.Heating program was determined by the pyrolysis behavior of PF

PEG and their blend (PF-PEG)in the heating process characterized by the TG.The specific surface area and pore structure parameter of the activated carbon were calculated by the N2-BET method.Galvanostatic charge-discharge

cyclic voltammetry and alternating current impedance were used to characterize electrochemical performance of activated carbon.Activation temperature

water vapor flow rate and activation time affected the pore structure and electrochemical performance of activate carbon.The results showed that with increasing activation temperature and increasing activation time

the capacitance increased.At activation temperature of 900℃

steam flow rate of 1 ml·min-1 and activation time of 2 h

the structure and properties of prepared activated carbon were better.Its pore size was mainly smaller than 2 nm.With electrolyte solution 1 mol · L-1 KOH/H2O solution，its capacitance reached 105.4 F·g-1 with a traditional three-electrode test system

and cycling performance was better.