Objective: Iron is needed for many enzymes to function normally, so a wide range of symptoms may eventually emerge in iron deficiency, including retardations in growth and maturation. Because of this it is reasonable to hypothesize that iron supplementation may affect the timing of tooth eruption. The purpose of this study was to examine the association between iron supplementation and tooth eruption. Materials and Methods: This study included children under the age of 3, who were admitted to Gülhane Training and Research Hospital, Clinic of Paediatrics for the well child follow up. Their parents were asked to complete a questionnaire including questions about the first tooth eruption time and about the iron supplementation history of their child, along with questions about the factors known to influence tooth eruption process. Results: There was a significant positive correlation between the duration of iron supplementation therapy of the children during infancy and eruption time of the first deciduous tooth (r=0.636 p=0.0001). While the duration of iron supplementation therapy increased, the eruption time of the first deciduous tooth was significantly later.Conclusion: The length of time a tooth is present in the oral cavity affects its risk for dental caries. Iron deficiency may cause oral hygiene and periodontal disease in the manner above by causing early eruption of deciduous tooth. The physicians giving iron therapy for supplementation can inform and encourage the parents in this way, to prevent the deprivation of this vital supplement by the parents.