Heme iron preparation( HIP) made from digested hemoglobin is known to be more readily absorbed by the human body than iron salts. In the present study, HIP was prepared from blood of cultured yellowtail, by denaturation of proteins, hydrolysis of hemoglobin using protease, and recovery of HIP by ultrafiltration. The dry mass, iron distribution, and molecular weight distribution of peptides in the permeate and the retentate after ultrafiltration were analyzed. Hydrolysis of hemoglobin using protease and quantitative recovery of HIP by ultrafiltration were confirmed. The molecular weight distribution of the resulting material as HIP was from 2,400 to 7,300. Efficiency of HIP recovery by ultrafiltration was compared using different ultrafiltration membranes. More than 95% of HIP was recovered by ultrafiltration using a membrane having a molecular weight cut-off of 20,000.