The effect of weekly iron supplementation and deworming on the hemoglobin level was studied among 289 children aged 2 to 5 years in a randomized double-masked placebo controlled community trial. Subjects were allocated into 3 groups which respectively received iron supplements and deworming, iron supplements only and placebos. Iron supplementation for 8 weeks using 30 mg elemental iron as ferrous sulphate syrup once per week, led to a significant reduction in the prevalence of anemia from 37.2%. to 16.2%. Using unsupervised distribution by mothers, hemoglobin concentration increased significantly in both groups which received iron (p<0.001) and also in the placebo group (p<0.05), but the changes in both treatment groups were significantly higher than the placebo group (p<0.001). No significant difference in hemoglobin changes was found between those who received additional deworming and those who received iron supplement only. Positive iron in stool were confirmed in 68.2% of the children who were reported received iron supplements (n=66). It is concluded that weekly iron supplementation is effective to reduce the prevalence of anemia among preschoolers.