Context: WHO reports that the viral dose in HIV transmission through blood is so large that one HIV positive transfusion leads to death, on an average after two years in children and after three to five years in adults. Transfusion medicine, apart from being important for the medical treatment of each patient, also has great public health importance. Objectives: The present study was conducted to estimate the prevalence of HIV infections in voluntary blood donors at a tertiary care teaching hospital in Mumbai. Materials and Methods: All voluntary donors reporting to the blood bank were screened for HIV by using the appropriate enzyme-linked immunosorbent assay. The study was designed for duration of seven years between January 2008 to December 2014. Medical reports of the donors were accessed from the blood bank records and analyzed. Results: A total of 5606 voluntary blood donors were screened, of which 5120 (91.33%) were males and 486 (8.67%) were females. The seroprevalence of HIV was 1.37%. Conclusion: Blood is still one of the main sources of transmission of HIV infections.