This study includes measurement of uranium concentration and calculates the specific activity in human blood samples (leukemia and health people) taken from some governorates of Iraq by using fission fragment track technique.The nuclear reaction used as source of uranium fission fragment is U-235 (n, f), obtained by the bombardment of U-235 with thermal neutrons from (Am- Be) source which has a flux of (5 x 103 n.cm-2. s-1 ) , the concentration values were calculated by comparison with standard biological samples which prepared.The highest rate of uranium concentration in human blood was (1.654 ppm) in Basrah governorate and the lowest rate of uranium concentration in human blood was (0.153 ppm) in Baghdad governorate. And also calculate the specific activity for human blood samples in those regions and found that the highest rate was (1.43 x 10 -1 Bq/g) in Basrah governorate and the lowest rate was (0.1258 x 10 -1 Bq/g) in Baghdad governorate.The highest of uranium concentration was (1.841 ppm) for leukemia sample in Al-Muthana governorate and the lowest uranium concentration was (0.364 ppm) in Diyala governorate, and the specific activity was calculated for leukemia samples and found that the highest activity was (1.79 x 10 -1 Bq/g) in Al-Muthana governorate and the lowest activity was (0.34 x 10 -1 Bq/g) in Diyala governorate.Uranium concentration results compared with permissible limit who purplish from ICRP agency and the specific activity calculations for human blood samples compared with permissible limit who published from IAEA agency.
