Phenol and its three chloro derivatives were electrooxidized on glassy carbon electrode under optimized conditions of concentration, number of repeated scans, scan rate, and pH of the medium. Next, the aqueous solutions of the phenols were degraded under controlled dose of gamma (gamma) radiations in the range of 1-5 kGy. The post gamma-irradiated phenols were investigated by cyclic voltammetry (CV) and the response was quantitated in terms of radiolytic yields (G values) and degradation efficiencies. The calculated theoretical charge densities were also in support of phenols degradation via hydroxyl radical attack. The proposed use of CV as a new monitoring method for the degradation of organic pollutants was validated with the well-established HPLC method.