Background : Iron deficiency anemia (IDA) is one type of anemia found most often in children in the world especially in developing countries such as in indonesia. The prevalence of the highest of iron-deficiency anemia (IDA) at the age of toddlers, occurring generally in the second year of life. Given the high risk of iron deficiency in infants and toddlers, then according to WHO iron supplementation can be supplied in masse. Besides Ikatan Dokter Anak Indonesia (IDAI) has also given the national recommendations for granting suplementasi iron. The purpose of this research is to find relation the provision of iron suplementation with the incidence of iron deficiency anemia on children aged 9-12 months. Methods : Subjects of this research is children that seek treatment and do a check hemoglobin level in PKU Muhammadiyah Gamping Hospital Yogyakarta which were 26 sample children aged 9-12 months. Subjects were divided into two groups, the group of cases and the control group. The case group was children with low hemoglobin levels, is the control group of children with normal hemoglobin levels. Data analysis used fisher test because sample less than 40 and there are a cell that value hope ( E ) less than 5. Research instrument used in this research are medical record and structural interview. Result : There are 12 ( 92,3 % ) children suffering from anemia who are not iron suplementation history, 1 ( 7.7 % ) children that is suffering anemia who were given suplementasi iron, 10 (76.9%) children without anemia who did not receive iron supplementation, and 3 (23,1%) children without anemia who were given suplementation iron (p = 0,593, odds ratio = 3,6). Conclusion : This research show that there is no correlation between the of iron suplementation with the iron deficiency anemia in children the ages of 9 – 12 months.