In this study an electrodeposition procedure of cobalt oxides operating under anodic condition and directly from 0.5M NaOH solutions containing 12mM gluconate and 12mM CoCl2 was defined for the modification of glassy carbon surface electrode. Different experimental approaches based on cyclic voltammetry, steady-state potentiostatic technique, chronoamperometry and scanning electron microscopy were used to characterize the deposited cobalt oxide films and to evaluate the kinetics and mechanism of electrodeposition. Some aliphatic aldehydes were tested as compound model in order to evaluate the electroanalytical properties of the electrodeposited cobalt film as active redox material for amperometric applications in strong alkaline aqueous solutions. Interesting results in terms of surface electrode modification “in situ” of glassy carbon substrate with cobalt oxides were obtained and critically discussed.