The invention discloses a flexible electrode with carbon fiber wrapped metal oxide for a capacitor and a preparation method. Through surface modification of metal oxide nanoparticles and the like, a flexible membrane that metal oxide nanoparticles are wrapped with a carbon nano fiber (a one-dimensional carbon material) is prepared by using an electrospinning technique, and the flexible membrane can be used in a flexible super-capacitor electrode. Not only is good flexibility achieved, a sufficient buffer space can be provided for volume variation of the metal oxide nanoparticles in operation through the carbon nano fiber, the volume effect of the metal oxide can be reduced, advantages of high specific capacitance, good stability and the like can be achieved, and the properties of a flexible capacitor can be further improved. In addition, methods such as surface chemical deposition or electric deposition are not needed in the production process, and the flexible electrode is simple to operate, controllable in material structure, low in cost and applicable to large-scale industrial production.