The mechanism of lead oxide formation during the potentiodynamic anodization of lead (Pb) electrodes in the region -0.95 to -0.35 V/SCE (Pb/PbO region) in 0.1 M NaOH + 0.1 M Na2SO4 at 80-degrees-C is discussed. X-ray diffraction and UV-visible reflectance studies suggest that beta-PbO initially forms on the Pb surface and gradually changes to alpha-PbO with increasing anodization time. In addition, the colour of the electrode changes from whitish yellow to reddish. The photoresponse for the lead oxide electrodes in 0.1 M Fe(CN)63-/4- decreases with increasing anodization time.