Supercapacitive properties of Single-walled carbon nanotubes/metal oxides nanocomposites (SWCNT-MO where M=Ni, Fe, Co) have been described. The SWCNT-MO nanocomposites was confirmed with SEM, EDX and XPS techniques. Supercapacitive properties of the modified electrodes in H2SO4 and Na2SO4 electrolytes was investigated using cyclic voltammetry (CV), galvanostatic constant current charge-discharge (CD) and the electrochemical impedance spectroscopy (EIS) techniques. SWCNT-NiO nanocomposite modified electrodes gave better supercapacitive performance with a specific capacitance of 186 mF cm−2 (or 928 F g−1). This value compared quite favourably and even higher than values hitherto reported in several literature.