Objective: To understand the current situation of physical health of children aged 3-6 years in Jiangsu Province, and to provide reliable basis and reference for the theoretical and practical work of children s physical health promotion. Methods: According to "National Physical Fitness Evaluation Standard Handbook(Children s Part)", the body shape and physical fitness indexes of 5 951 children in Jiangsu Province were measured and analyzed. Results: Overall proportion of standard physical constitution among children aged 3-6 in Jiangsu Province was 79.8%, which was lower than the national average level in 2020 (94.4%). Among them, the excellent rate, good rate and compliance rate of boys in comprehensive evaluation were higher(4.3%, 15.7%, 80.3 %) than those of girls(3.6%, 15.3%, 79.2%); The height and weight of children were generally higher than the national level in 2020; The strength and explosive power of children s lower limbs was lower than the national level in 2020( t=11.56, P <0.01); The flexibility and physical balance of older children in Jiangsu Province were relatively good. Conclusion The physical fitness level of 3-6 year old children in Jiangsu Province has increased steadily, especially physical flexibility and physical balance ability However the related qualities such as lower limb strength, explosive power and coordination need to be paid attention to and improved. It highlights the importance of monitoring, management and promotion of children s physical fitness.