In this study, transferrin which is an iron-carrying glycoprotein in plasma was evaluted for its iron binding capacities(TIBC), iron solubilizing abilities, and enhancing effect of biological availbability of iron. Results of TIBC showed that 1 mg of transferrin could blind 1.28$mu extrm{g}$ of iron indicating that one molecule of transferrin can bind about 2 molecules of iron. Also, solubility of iorn (7.5$mu extrm{g}$ Fe/ml) was significantly incresed to 96.0% with addition of transferrin (5mg/ml) .When FeCl3(80$mu extrm{g}$ Fe/ml) was injected to iron-deficient rats by intestinal segment in situ technique, 18.4% of injected iron was absorbed wherease 48.49 and 48.76% of injected iron was absorbed with addition of 10 and 20 mg transferrin/ml , respectively.