One dimensional carbon nanofibers embedded amorphous cobalt oxide with high electrochemical performances were successfully prepared by electrospinning Co(NO3)(2) in PAN/DMF solution followed by a high-temperature heat treatment process. The different molar ratio of AN/Co(NO3)(2) were synthesis. The optimized Co/CNFs(30), in which the molar ratio of AN/Co(NO3)(2) was 30/1, exhibited a specific capacitance of 1096 F g(-1) at 1 A g(-1) and almost no decay in specific capacitance after cycling 2500 times at 5 A g(-1). The Co/CNFs were characterized by scanning electron microscopy, X-ray diffraction, Raman, transmission electron microscopy, X-ray photoelectron spectroscopy, thermal-gravity-analysis and the N-2 adsorption-desorption. The result showed that cobalt element was successfully dispersed in the carbon nanofibers with an amorphous state.