For the electric double layer capacitors(ELDC) made of phenol based activated carbon fiber(ACF) electrodes and organic electrolytes, the specific capacitance characteristics has been investigated with respect to different specific surface area of electrodes and different kinds of organic electrolytes. Throughout charge-discharge cell tests, it has been found that larger surface area and larger pore diameter of electrodes contribute to increase the specific capacitance. Binary mixture of organic solvent with 1M-propylenecabonate(PC) and 1M-tetrahydrofuran(THF) for 1M-LiClO₄ electrolyte has a higher specific capacitance than single solvent of 1M-PC or mixed solvent with 1M-PC and 1M-diethylcabonate(DEC). Also, even though 1M-tetraethyl-amoniumperclorolate(1M-TEAPC) of organic electrolyte shows higher specific capacitance, it has longer charge time because of its lower ion mobility