The results of theoretical and experimental studies of the influence of Ba-atom implantation and the presence of an oxide film on the Si-surface sputtering coefficient under ion bombardment are presented. It is shown that, in the dose range of D = 1014–5 × 1015 cm—2, the Si sputtering coefficient increases linearly, then this increase decelerates, and is almost constant, starting from 1016 cm–2. In the range of D = 5 × 1015–5 × 1016 cm—2, the Ba sputtering coefficient increases sharply, which is explained by an increase in the Ba concentration in the surface layer during the ion bombardment process.