summary Transfusion-transmitted infections (TTI) continue to be a major challenge for Blood transfusion organizations across the world. The problem is more serious in the developing countries with lower economic means. Multitransfused patients (MTPs) in these countries are at higher risk of infection, and studies of infection in these patients can be a useful index for examining the blood safety filters in place. The present article reviews the situation in Iran, where prevalence of the major viruses of concern, namely, hepatitis B virus, hepatitis C virus (HCV) and human immunodeficiency virus, studied in these patients is reported over a 9-year period. It is demonstrated that HCV is the most prevalent TTI and remains a major health problem for these patients.