In order to approach the effect of different source Fe on piglet's growth, metabolism and environment, an experiment was conducted with 158 suckling pigs from 15 litters, which were randomly allocated to group I, II and III, and fed with diet I (basal diet + FeSO4.H2O), II (basal diet + Fe-citric acid) and III (basal diet + Fe-methionine complex), respectively. Each of the diets contained 146 mg.kg-1 Fe. The results show that after the experiment ended, the body weight, daily increment, grades for appearance and behavior, hemoglobin concentration in blood, Fe-transferring albumen concentration...