A 14-month-old boy was referred to our hospital for evaluation of severe anemia. In the bone marrow aspiration smear, normal cellularity with severe erythroblastopenia (3%) was observed. The hemoglobin electrophoresis of the patient and his father were compatible with the beta-thalassemia trait. Because macrocytosis of Diamond-Blackfan anemia (DBA) is masked by microcytosis of beta-thalassemia trait, the diagnosis of DBA co-existing with beta-thalassemia trait might be challenging. We report herein a case of DBA co-existing with beta-thalassemia trait in a Turkish boy.