Abstract: The growth process of PbO2 formed by the oxidation of PbSO4 in the anodic film on lead-(1,3,5,7)wt%antimony electrodes was investigated with impedance tracing method of single frequency and the current-time transient method. The influence of antimony on this process was studied.The simulation curves obtained for capacity-time transients fit the experimental results very well.It has been shown that the mentioned growth process is a two-dimentional instantaneous nucleation and growth process,Antimony will inhibit the growth of PbO2 nucleus but enhance its nucleation.