Background: Children with bleeding disorders, such as hemophilia and von Willebrand disease (VWD), have an increased risk of acquiring transfusion-transmitted infections (TTI). Screening methods to exclude blood donations that are at risk of transmitting infection from donors to recipients are critical to preventing disease transmission. Nucleic acid testing (NAT) is the latest blood donor-screening method. This study aimed to determine the incidence of hepatitis C virus (HCV) infection in children with hemophilia and VWD at Dr. Cipto Mangunkusumo Hospital with a history of blood transfusion before and after implementation of a NAT screening method. Methods: A cohort retrospective study was conducted on children aged 0‒18 years with bleeding disorders and a history of blood transfusion. In our center, all blood transfusions before 2015 were screened using non-NAT methods, while all blood transfusions were screened using NAT starting in 2015. Eligible patient characteristics were collected from medical records. From July to December 2019, blood samples were obtained from eligible patients for anti-HCV examination. HCV RNA examinations were performed on subjects with reactive anti-HCV results, and the relative risk was calculated. Results: In total, 108 eligible participants were included in this study. We observed that 91 (94.3%) patients had history of receiving non-NAT blood transfusions, while 17 (15.7%) patients received NAT-screened blood transfusions. The proportion of anti-HCV reactivity in the non-NAT group and that in the NAT group were 3.3% (3/91) and 0% (0/17), respectively. Conclusion None of the patients exhibited reactivity to anti-HCV after implementing the NAT screening method.