Degradable pure iron stent or iron alloy stent containing 0.01 to 0.5 atom% of La, Ce or Sr are surface modified using ion implantation or plasma ion implantation to implant oxygen, nitrogen, La, Ce or Sr into the stent surface, or to deposit a thin film of La, Ce, Sr, lanthana, ceria, strontia, iron or iron oxide onto the stent surface. The thickness of the deposited films is from 10 to 1000 nanometers with the grain size from 10 to 200 nanometers. The corrosion resistance of these stents is significantly increased, and the stents have good biocompatibility. The degradation of the stents is controllable. The stents can also provide sufficient support in blood vessel in 3-6 months after intervention and be degraded after 6 months.
