In this work, molecular and genetic analysis of p - thalassemia in a sample of Iraqi population was made. The study included hematological screening of peripheral blood cells, analysis of protein profile, molecular analysis of B - globin gene, and Pedigree analysis for patients, and carriers in comparison with normal people. The first part included hematological prescreening for 50 patients with P - thalassemia anticipated Ibn - Albaladi hospital from different geographical regions of Iraq. The hematological tests were PCV, MCH, and MCV. Results obtained showed that PCV was 20 - 25 % for patients; and 30 - 38 % for carriers (parents), MCH was 27 pg for patients; and 20 - 25 pg for carriers, MCV was 47 fl for patients; and 60 - 65 fl for carriers. Moreover, hemoglobins F, A, A2 were also determined using electrophoresis that showed 90 % of patients had high ratio of HbF and HbA2, whereas low level of HbA was found in comparison with normal people for both patients and carriers. In addition, it was found that there is a change in RBCs, and WBCs configuration since RBCs took abnormal shapes as a reflection to the disease and there is an increased level of reticulocytes in both patients and carriers but with less severity in carriers. The WBCs were at increased levels, especially eosinophils, and others like nutrophils, lymphocytes, and monocytes as a result of splenoctomy and pathogens infection during transfusion in patients, whereas they were at normal levels in carriers. The second part of this study included analysis of protein profiles of patients and carriers with B- thalassemia syndrome. Four electrophoresis techniques were used and results obtained showed that there is a remarkable difference in protein profiles in patients and carriers in comparison with normal since the B - chain was not detected in patients-with sever form of thalassemia, and only a part of this chain was found in carriers. The y - globin, and a - globin levels were increased in patients and carriers in comparison with normal people. The third part of the work had focused on molecular analysis at DNA level for Iraqi families with B - thalassemia using specific primer PCR amplification. The results showed the presence of point mutation in B - globin gene in patients with thalassemia major (homozygous) that led to complete depression in gene expression, whereas heterozygous (carriers) showed only partial expression in B- globin gene in comparison with normal people since it occurred in one allele of the gene. Fragments sizes obtained from PCR amplification were 185, and 190 bp. These results were good indication for the type of mutation causing B- thalassemia in Iraqi population, which was concluded to be point mutation causing inactivation of B - globin gene. This is the first study concerning the molecular level and mutation type in Iraq to be compared with neighboring Arab Countries. The fourth part of the study included Pedigree analysis of families with B - thalassemia syndrome that was made depending on data obtained previously and family history. The analysis showed the transfer of the trait among generations, especially in families preferring marriage of relatives.