Hydrogen gas re-emission and scanning electron microscopy measurements were conducted on a series of cold-worked Types 316 and 302 stain-less-steel specimens implanted with 20-keV protons at temperatures from 100 to 605 K. Two mechanisms of hydrogen release were observed by a dose of 5 × 1018 H+/cm2, while at higher temperatures there was a rapid hydrogen evolution without any extensive surface deformation.