Porous Co3O4 nanostructured thin films are electrodeposited by controlling the concentration of Co(NO3)2 aqueous solution on nickel sheets, and then sintered at 300°C for 3h. The as-prepared thin films are characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The electrochemical measurements show that the highly porous Co3O4 thin film with the highest electrochemically active specific surface area (68.64m2 g−1) yields the best electrochemical performance compared with another, less-porous film and with a non-porous film. The highest specific capacity (513mAhg−1 after 50 cycles) is obtained from the thinnest film with Co3O4 loaded at rate of 0.05mgcm−2. The present research demonstrates that electrode morphology is one of the crucial factors that affect the electrochemical properties of electrodes.