Alpha thalassemia is inherited as one of the most common cause of hemolytic anemia in children. The objective of the study was to identify the carriers and the mutations on a globin gene and to design a method to diagnose a thalassemia by PCR and sequencing technique. Results: 1. 5 types of common mutations were detected on a globin. (--SENaa): 50 percent, (-HbCs/aa): 32.4 percent and 1 rare point mutation -c.2deIT/a a): 4.6 percent. 86.4 percent couples with hydrops fetalis are alpha thalassemia carriers (--SENaa). 2. 4 fetus of HbH, 14 fetus of Hb Bart's,. 10 normal fetus 22 heterozygote fetus were diagnosed prenatal. In conclusion, prenaral diagnosis for alpha Thalassemia is the most effective method to prevent and control alpha thalassemia.