The kinetics of oxidation of iron surface has been studied by AES method. The effects of oxygen diffusion into the lattice defects have been considered in the discussion of the mechanism of the oxygen adsorption. The real sticking coefficient has been determined as a function of oxygen coverage (S=1– in the range of 0<0.9). the="" oxidation="" of="" iron="" surface="" occurs="" in="" two="" steps.="" at="" the="" first="" step="" the="" dissociative="" oxygen="" adsorption="" occurs="" for="" the="" coverage=""> _O<1 and="" the="" rate="" of="" the="" oxygen="" molecule="" adsorption="" is="" limiting.="" at="" the="" second="" step,="" in="" the="" range="" of="" oxygen="" coverage=""> _O<2, the="" reconstruction="" of="" the="" iron="" surface="" occurs="" with="" the="" formation="" of="" free="" adsorption="" sites.="" at="" this="" step="" the="" sticking="" coefficient="" of="" oxygen="" is="" almost="" constant="">S0.1).