Abstract: HNO₃-oxidized single-wall carbon nanotubes (SWCNTs) and graphene oxide (GO) were ultrasonically dispersed in water to which potassium permanganate was added, and the resulting mixtures were treated under microwave radiation at 100℃ for 1h or hydrothermal conditions at 100℃ for 1, 5 and 10h to prepare SWCNT-GO/MnO₂ composites as electrode materials of electrochemical capacitors. Results indicate that the composite prepared using the microwave method has a higher specific capacitance (173F/g at 0.2A/g), lower pseudo-charge transfer resistance (1.425 Ω) and longer cyclic stability (3.74% capacitance loss after 1000 cycles at the scan rate of 20mV/s) than the ones prepared using the hydrothermal method. Moreover, the microwave method has the advantages of simplicity of operation and shorter heating time.