Abstract: Iron deficiency is a widespread major micronutrient malnutrition problem for human beings, and it is believed to affect body health and economy development in the world. The problem of iron deficiency in human is due to an insufficient amount and poor bioavailability of iron in staple foods. Strategies for alleviating iron deficiency include medication, food diversification, food fortification, and biofortification combined with agronomic fortification. Biofortification approach through agriculture has been recognized as a sustainable, relatively simple, and realistic way to reduce and prevent iron deficiency. However, recent studies indicate that iron absorption is dependent on the bioavailable iron, rather than on total amount of iron in meals. The objectives of this paper are to review on the advances in studies of genotypic differences in iron content, iron bioavailability and their affecting factors, and to analyze the advantages and disadvantages of several methods for assessing iron bioavailability from plant-source foods.