In the present work, the corrosion behavior of a double-layer stent, which is the combination of an uncoated outer stent and silicon-coated body stent, was assessed by the use of electrochemical methods in phosphate buffered saline solution at 37 °C. Although each stent comprising the double-layer stent showed favorable corrosion properties, the double-layer stent showed a significant diminishment of these corrosion properties. Also, the corrosion was focused on the uncoated outer stent on the double-layer stent and the instability surface condition was observed in the double-layer stent. The cathodic reaction was activated on the outer stent of the double-layer stent by the galvanic effect, and the hydrogen thus generated was detrimental to the surface film. In addition, hydrogen had a synergic effect with chloride and accelerated the corrosion reaction on the outer stent.