Formaldehyde was degraded with hydrogen peroxide and hypochlorite ion electrogenerated by paired electrolysis of dissolved oxygen and chloride ion in aqueous solution. Degradation of formaldehyde in the cathodic compartment was significantly affected by the ratio of electrolyte volume to cathodic surface area, oxygen sparging rate and stirring rate. The model calculations correlated sufficiently well with the experimental results. The average current efficiency and degradation fraction of the in situ paired electrooxidative degradation of formaldehyde were experimentally found to be 62.0% and 93.2%, respectively.