Objective: To analyze the influencing factors and physical and mental development of preschool children with iron deficiency anemia in Dongguan, so as to provide a reference for the prevention of iron deficiency anemia among preschool children. Methods: A total of 118 preschool children with iron deficiency anemia who were examined in Dongguan Maternal and Child Health Center from January 2022 to December 2022 were enrolled in the anemia group, and 118 preschool healthy children who were examined in the hospital at the same time were enrolled in the control group. The physical and mental development of the children were evalucded in both groups. Demographic information and household per capita income were collected. The relationship between risk factors and iron deficiency anemia was analyzed by univariate analysis and multiple Logistic regression. Results: The scores of fine motor skills, gross motor skills, adaptability, social communication, language ability and developmental quotient of children in anemia group were significantly lower than those in control group ( t =4.14, 5.46, 5.60, 5.50, 4.90, 5.83, P <0.01). The difference in scores of adaptability, fine motor skills, gross motor skills language ability, social communication and developmental quotient between the two groups increased with age ( F =390.56, 414.63, 437.35, 409.68, 407.20, 404.54, P < 0.05 ). Multivariate Logistic regression analysis showed that household income, history of past digestive disease, gestational age, maternal anemia during pregnancy, maternal education, consumption of meat, eggs and milk, and intake of nuts were all associated with iron deficiency anemia among preschool children in Dongguan ( OR =2.23，2.99，3.99，3.56，3.11，1.68，1.61, P < 0.05 ). Conclusion The physical and mental development of preschool children with iron deficiency anemia in Dongguan is slower than that of non anemia children of the same age, and the development delay becomes more obvious with increasing age. Attention should be paid to the prevention of iron deficiency anemia among preschool children. It is important to provide reasonable dietary guidance for children with high risk factors such as digestive disease history and prematurity.