SUMMARY. Peer victimization is a great social concern among school-aged children that can negatively affect their physical and psychological health and those with chronic illnesses such as thalassemia are at an increased risk. The aim of the present study was to assess peer victimization and its effect on psychosocial health among children with thalassemia at Zagazig University Hospital. A case-control design was conducted on a matching sample of 47 children with thalassemia at Pediatric Hematology outpatient clinics at Zagazig University Hospital and 47 controls at four schools in Sharkia Governorate, Egypt. Six tools were used; a structured interview questionnaire, Multidimensional Peer-Victimization Scale, Self-Perception Profile for Children, Reynolds Adolescent Depression Scale, Multidimensional Anxiety Scale for Children and UCLA Loneliness Scale. The results revealed that children with thalassemia were less victimized than children in the control group and the result was statistically significant (p < 0.05). Also, there was negative correlation between peer victimization and both; self-perception (r = -0.241) and social acceptance (r = - 0.274) and positive correlation between peer victimization and depression (r = 0.578), anxiety (r = 0.368) and loneliness (r = 0.447). It could be concluded that when the child is more prone to peer victimization, he will be at increased risk for depression, anxiety, loneliness and decreased self-perception It could be recommended that specific anti-victimization programs that targeted at improving acceptance, and positive interactions between children and their peers should be implemented to lower the level of victimization.