This study is described for the RAMS activities of performed to 2008.12 ~ 2010.10 KTX CTC Project. RAMS activities follow EN50126, EN50128, EN50129. CENELEC standards(EN50126, EN50128, EN50129) to the System Development Life-cycle are defined. This study is RAMS activities of life-cycle that can be found to satisfy SIL2. In addition, assessment of the ISA was completed. This paper is describe RAMS activities results of each phase and Safety Case according to Verification / Validation result.