Abstract: The paper presents the preliminary corrosion results of Ti--modified type 316stainless steel exposed to 650℃ sodium up to 10000h. These investigations arecarried out in the thermal convective sodium loop with vaccum--inerts glove boxand prepare to gain basic information on corrosion behaviors of Ti--modifiedtype 316 stainless steel and useful practical experience in sodium technology.Weight gain, microstruture changes due to sodium exposure are observed and thedeterminations of the concerned parameters are also carried out.