Abstract: Nitinol alloy has been widely used as an implant material. However as an endoluminal implant material, more studies on its biocompatibility should be done. The authors reported this study on endotracheal implantation of nitinol alloy. The results showed that there were no evidence of either generalized or localized corrosion on the surface of all 10 specimens over a period of 1 to 6 months, the shape-memory property remained unchanged. The specimens were gradually surrounded by fibrous capsules and covered by regenerated ciliated epithelium. The nickel concentration was not significantly increased in the liver, heart and trachea. It is suggested that nitinol alloy is an ideal endoluminal implant material.