Nanoflakes of the cobaltous oxide as a thin film were deposited from a 100mM cobalt (II) nitrate solution potentiostatically at −1000mV (vs. Ag/AgCl) onto a platinum electrode surface. Surface morphology of the cobaltous oxide was studied by surface microscopy techniques (SEM, AFM and STM) and the electrochemical behavior was evaluated in alkaline solution using cyclic voltammetry and electrochemical impedance spectroscopy. Using cyclic voltammetry, the electron-transfer coefficient and the apparent charge-transfer rate constant of various redox transitions were determined. The cobaltous oxide electrode represented prominent electrocatalytic activity toward the mediated electrooxidation of ascorbic acid, glucose and methanol. In the Nyquist diagrams, different time constants appeared with relation to different physicochemical processes.