Background:The present study was undertaken for assessing Individual Donor Nucleic Acid Test (ID-NAT) For Human Immunodeficiency Virus 1 & 2 and Hepatitis B & C Virus in Blood Donors. Materials & methods:The present study was undertaken for assessing Individual Donor Nucleic Acid Test (ID-NAT) For Human Immunodeficiency Virus 1 & 2 and Hepatitis B & C Virus in Blood Donors. All the blood samples of blood donors were screened by ID NAT and ELISA for HIV1&2, HCV and HBV. Samples from donated blood units would be screened by ID NAT byProcleix® Ultriopluselite® Assay (Panther® Grifols Diagnostic Solutions Inc. Emeryville, USA)and by Enzyme-Linked Immunosorbent Assay (ELISA). Results of ELISA and NAT tests were compiled every day. Units which were reactive by any tests were segregated and kept in quarantine area, and sent for disposal using biohazard labels. We assessed the seroprevalence of HIV1&2, HCV and HBV by ID NAT testing among the entire voluntary and replacement donors between 18-65 years of age. All the results were recorded in Microsoft excel sheet and were analysed by SPSS software. Results:A total number of 26474 blood donors were screened for HIV-1 & 2, HCV & HBV over duration of one year. Out of them, 13998 were voluntary donors and 12476 were replacement donors. Among total 741 reactive donors 587 donors were first time donors and 154 donors were repeat donors. Out of total 360 (48.9%) replacement reactive samples 222(61.6%) samples were sero positive NAT positive, 112(31.1%) and 26(7.2%) were reactive only by NAT. among 381(51.1%) voluntary reactive samples,206(54%) were reactive on both serology and IDNAT,239(33.3%) samples have sero yield and 48(12.6%) were ID-NAT yield samples. Conclusion:It was detected that 74 donor sample which were reactive by ID-NAT only they were non-reactive on serology. 222 patients were protected from above mentioned viral infections who were going to receive blood and blood components donated by these 74 NAT reactive donors which were missed by serology assay because of window period.