Abstract: Ferritin was purified from human liver by Frenkel method. Molecular weight of ferritin subunit was 20. 5 kD. Rabbit serum of anti-human liver ferritin was prepared with the titre of more than 1: 50000 and affinity constant K, of more than 1.2×10~9 1/mol. ~(125)I-ferritin prepared by chloro-amino T has the radiochemical purity of more than 955,specific activity of 1.3×10~6 Bq/μg and binding rate of superquantity antibody of more than 80%. Analytical method of RIA was established, the sensitivity, was 1.9±0.5 ng/ml, the rate of recovery Was 98±5%, the coefficients of variability for intraassay and interassay were< 4.2% and <8.5% respectively. Serum ferritin concentration was measured in 303 healthy persons and 136 relative patients. The results agree with the clinic diagnosis.