Abstract: Objective To investigate the prevalence of iron deficiency anemia in infants of 6 months old and its determinants at a community of Shanghai.Methods One hundred and ninety 6-month-old infants born from Jan 2007 to Jun 2009 at a community of Shanghai were randomly selected as subjects, whose hemoglobin(Hb) levels were tested, with related influencing factors investigated.Results The prevalence rate of iron deficiency anemia in infants in this community was 21.58%. Both univariate analysis and multivariate Logistic regression showed that the feeding pattern within 6 months and adding supplementary food within 4-6 months were the determinants of iron deficiency anemia of infants, with the OR of 3.0 for group of pure breast feeding within 6 months and 19.8 for non-adding supplementary food within 4-6 months respectively.Conclusion At the time as breast feeding is encouraged, it should be made known that supplementary food be added and iron element be timely replenished so as to effectively decrease the incidence of iron deficiency anemia in infants.