Background: Anemia is a major health problem throughout the world andchildren under 5 years of age are at highest risk. Nutritional deficiency isthe mostcommoncauseofanemiainchildrenunder2yearsofageduetohighrateofgrowthandincreaseddemandofiron,vitaminB12andfolicacid.According to WHO, 1 out of every 2 pre-school children are suffering from IDA indevelopingcountries. Different oral iron preparations are available totreatIDA.Hence, this study was done to compare the therapeutic efficacy andside effects offerroussulphatewithcolloidalironinthetreatmentofIDAinchildren. OBJECTIVES: 1. TocomparethetherapeuticefficacyofferroussulphatewithcolloidalironinthetreatmentofIDAinchildrenaged6monthsto18years. 2. Tocomparethesideeffectsbetweenthetwogroups. Methods: This randomizedcontrol study was conducted in MVJ medicalcollegeandresearchhospital,Hoskote,Bangalore.Eligiblechildrenwererandomized to 2 groups. Group A consisting of 75 children were given ferroussulphateinadoseof3mg/kg/dayofelementalirononcedailyfor4weeks.GroupBconsistingof75childrenweregivencolloidalironinadoseof3mg/kg/dayof elemental iron once daily for 4 weeks. Reticulocyte countbetween the twogroupswas checked at the end of one week and haemoglobinat the end of onemonth. Side effects and compliance of the two ironformulations were checked onfollowup. Results: The mean rise in the reticulocyte count at the end of 1 week is higherincolloidalironincomparisontoferroussulphategroup.Themeanriseinhaemoglobin at the end of one month is more in colloidal iron compared to ferroussulphate group, however the difference is not statistically significant. Compliancewith colloidal iron is better than ferrous sulphate group, as nausea is comparativelymorewithferroussulphategroupwhichattributedtodecreasedcompliancewhichisstatisticallysignificant. Conclusion: Colloidal iron and ferrous sulphate are found to be equallyefficacious in thetreatment of iron deficiency anemia. However, owing to its goodcompliance and lesser GI side effects, colloidal iron is found to bepreferable overferroussulphate. Hence, the study suggests the use of colloidal iron to treat IDA in children between 6 months to 18 years.