Transfusion-transmitted infections including hepatitis B virus (HBV) have been a major public health concern worldwide. Occult HBV infection (OBI) is defined as the presence of HBV DNA in the liver (with detectable or undetectable HBV DNA in the serum) of individuals who tested negative for HBsAg. Clinically, OBI is considered a risk for viral reactivation and possible transmission of infection among individuals. It also contributes to liver disease progression and development of hepatocellular carcinoma. Better knowledge and strategies to prevent, diagnose and manage must be implemented in this field. The aim of this study was to estimate the prevalence of OBI among multi-transfused patients in the northern districts of the occupied Palestinian territories. A prospective cross-sectional study was conducted in the period from August 2016 to May 2017 on 169 who were negative for HBsAg and received more than 10 units of packed RBCs throughout their lives were included in the study. Blood samples were tested for HBsAg, anti-HBs and anti-HBc by ELISA. Those positive to anti-HBc were then retested for HBV DNA, using an automated real-time PCR method. Among the 169 HBsAg- negative sera, anti-HBc was detected in 35 patients (20.7%). All anti-HBc-positive patients were HBV DNA-negative, and 27 (77.1%) of them were anti-HBspositive. Based on our results, it seems that there were no cases of OBI among poly-transfused patients with thalassemia and sickle cell anemia. However, to improve decisions concerning OBI screening, especially in transfusion centers, more original studies with more precise laboratory techniques and larger sample sizes are needed.