Sputtering yields of metal ion beams on polycrystalline films for energies below 1 keV were measuredin situusing crystal microbalance techniques. Self‐sputtering yields were determined for Au, Cu, Ag, Cr, and Al for energies from 10 to 500 eV. These yields were consistent with some previous noble‐gas sputtering yields when only the difference in ionic mass was taken into account. Residual oxygen significantly lowered the self‐sputtering yields of Al and Cr for all energies from 0 to 1 keV and the collection rate of oxygen was apparently greater for ions of about 10 eV. Sputtering yields of films by dissimilar metal ions were most strongly influenced by the type of metal in the beam, rather than by the target material, even for high ion energies.