Background:Worldwide most deaths and disability related to blood transfusion is still caused by the transfusion transmitted infectious agents; viruses, bacteria or protozoa. The DGHS of India and CDSCO mandated 5 tests for blood to be transfused that are HIV, HBV, HCV, Malaria and Syphilis.2,3 In this retrospective study we are going to find out the Seroprevalence of transfusion transmitted infections among voluntary non-remunerated blood donors and replacement donors. Methods:The retrospective study was carried out in the blood centre, IOG&WCH, MMC, Egmore cennai-08. The study period is 5 years (June 2018 to December 2022). The HIV, HBV and HCV are tested by ELISA method (HIV 4th generation & HBV, HCV 3rd generation ELISA) by using commercially available kits as per the instruction manuals.Result:The seroprevalence among the VNRBDs is 3/14448 (0.02%) for HIV, 85/14448 (0.6%) for HBV, 7/14448 (0.04%) for HCV, and 5/14448 (0.03%) for Syphilis. Similarly the reactivity rate among the replacement donors is 11/8855 (0.12%) for HIV, 130/8855 (1.5%) for HBV, 16/8855 (0.18%) for HCV, and 8/8855 (0.09%) for Syphilis.Conclusion:Highly sensitive screening techniques along with implementation of NAT, appropriate donor counseling and education, proper implementation vaccination will help to enhance the quality of blood and blood products.