This study aims to investigate the prevalence of overweight and obesity in preschool children in Hangzhou and assess the impact of childcare management. By examining the characteristics and predicting the trends of overweight and obesity, we hope to emphasize the significance of childcare management in primary community health service centers and the use of Electronic Health-care System in kindergartens. This study also seeks to provide evidence for intervention measures and effective prevention and control management of childhood obesity. From 2020 to 2022, kindergarten children aged 3-6 years old were selected as the research objects in kindergartens in Hangzhou. The Electronic Health-care System will be utilized to facilitate the management of childhood obesity and provide guidance and training to pediatricians and Primary Care Physicians. The overall detection rates of overweight and obesity were 7.27 % and 3.55 %, respectively, among children aged 3-6 years in Hangzhou. The rates of simple obesity in Hangzhou preschool children aged 3-6 years were 4.25 , 3.42, and 3.04 % from 2020 to 2022, respectively; the overweight detection rates of children were 8.27 , 7.28, and 6.34 %, respectively, and the difference was statistically significant (p<0.05). The detection rates of overweight and obesity in 2022 were significantly lower than those in 2020 (p<0.05). The prevalence of obesity in children increased with age. Boys had a significantly higher incidence rate of obesity than girls (p<0.05). The proportion of children with moderate and severe obesity showed a downward trend. Intervention measures for childhood obesity in primary community health service centers and kindergartens are constantly being implemented. The prevalence of obesity in preschool children aged 3-6 years in Hangzhou exhibited a decreasing tendency. This research has identified that child care administration, particularly the implementation of the Electronic Health-care System, demonstrates effectiveness in handling overweight and obesity amongst children.