Abstract: NiTi alloy with near-atomic ratio is widely used in medical area due to its unique shape memory effect and super elastic. But recent researches indicate that Ni+ can result in toxic reaction of the human body, even is carcinogenic, this factor constrainting its application in biological medical material area. In order to inhibite the release of Ni ions, surface modification of NiTi alloy can effectively improve the security using. The present paper describes research progress on surface modification of NiTi alloy in recent years, and discusses the TiO2 surface modification of porous NiTi alloy for medical development prospects.