A mathematical model of iron deposition on the rotating disk electrode (RDE) in the presence of surface inhibitor is presented. The model describes the plating process by incorporating the mass transport of participating ionic species, homogeneous chemical reactions within the diffusion layer, adsorption phenomena of hydroxyl ion and surface agent, and the associated electrochemical kinetics. Iron deposition rate can be predicted as a function of disk rotation speed, solution pH, bulk concentrations of participating ionic species. It is shown that iron deposition rate is inhibited in the presence of surface additive due to the less available electroactive area. Model results indicate that higher ferrous ion concentration can be preserved at the interface in the presence of additive so that higher potential can be applied without concentration depletion within the diffusion layer.