Objective: To explore the moderating role of estradiol in the relationship between parenting styles and preschool children's behavioral problems, so as to provide a theoretical basis for improving the development of human s emotional health development in early life stage. Methods: During September to November in 2022, 354 children aged 3-6 years and their parents from two kindergartens in Bengbu City were chosen by using stratified cluster sampling method for the questionnaire survey. The Parenting Style Scale and the Child Behavior Checklist (CBCL) were used to collect information on parenting style and child behavioral problems. Salivary estradiol of children was collected and tested. Independent samples t test was applied to compare the scores of the scale for parental up bringing and children s behavioral problems, and Pearson correlation analysis was conducted to explore the relationship among parental upbringing, estradiol and children s behavioral problems. Results: Parents doting, laissez faire, autocratic, and inconsistent parenting styles were positive associated with child behavior problems( r =0.14-0.70); fathers democratic parenting style was negatively associated with child behavior problems( r =-0.14，-0.22，-0.21，-0.17，-0.27，-0.20); mothers democratic parenting styles was negatively correlated with scores on all five dimensions of child behavior problems except the withdrawal dimension ( r =-0.14，-0.12，-0.13，-0.21，-0.12)( P <0.05). Estradiol levels had significant moderating effects on maternal doting parenting style and children s withdrawal ( β =0.68) as well as social problems ( β =-1.00), also moderating laissez faire parenting styles and children s withdrawal problems ( β =0.75)( P <0.05). For children with low levels of estradiol, withdrawal problem scores were negatively associated with mother s doting parenting style and positively associated with laissez faire parenting style, and socialization problem scores were associated with mother s doting parenting style; for children with high levels of estradiol, withdrawal problem scores were positively associated with mother s doting parenting style, and socialization problem scores were associated with mother s doting parenting style ( t=2.84, 6.24, 3.16 , 2.37, 4.49, P <0.05). Conclusions Parenting styles are strongly associated with child behavioral problems; estradiol levels play a moderating role in mothers doting, laissez faire parenting styles and children s withdrawal problems and social problems.Parents should adopt more positive parenting styles and focus on the role of estradiol levels in maternal education to reduce the occurrence of behavioral problems in children.