Abstract Objective To investigate the physical fitness level and health behavior status of preschool children in China, explore the relationship between physical fitness and health behavior, and further reveal the main factors affecting health behavior, to provide a reference for improving the physical fitness level of preschool children and maintaining healthy behavior. Methods A total of 755 preschool children (394 boys and 361 girls, aged 4.52 ± 1.11 years) were selected from Chongqing and Liupanshui in China by cluster random sampling method for questionnaire survey and physical monitoring, and SPSS21.0 software was used to process and analyze the data. Results (1) Heart rate ( p = 0.015), protein content ( p < 0.001), and time spent on the balance beam ( p < 0.001) were significantly lower in boys than in girls, while BMI ( p = 0.012), muscle mass ( p < 0.001), and distance of standing long jump ( p < 0.001) were significantly higher in boys than in girls. Meanwhile, systolic blood pressure ( p = 0.004) and diastolic blood pressure ( p = 0.001) of rural children were significantly higher than those of urban children, while BMI ( p < 0.001) and sitting forward flexion ( p = 0.019) were significantly lower than those of urban children. (2) The light-intensity physical activity (LPA) and moderate to vigorous physical activity (MVPA) of boys were significantly higher than that of girls ( p < 0.001), and the MVPA of urban children was significantly higher than that of rural children ( p = 0.001), and the former participated in sports classes more frequently ( p < 0.001). (3) There was a significant correlation between physical activity (PA) and physical fitness indicators of preschoolers. Participating in sports interest classes was only significantly correlated with systolic blood pressure ( r = 0.08) and sitting forward flexion ( r = 0.09). (4) The PA level of preschool children was related to gender, household registration, kindergarten nature, age, residence environment, parental support, and participation degree. Participation in sports interest classes was related to gender, the nature of the kindergarten, household registration, age, and parent participation. Daily screen time was related to household registration, the nature of the kindergarten, the environment of residence, and the value perception of parents. Conclusions There were different degrees of correlation between preschool children’s physical fitness and health behaviors, and children’s health behaviors were closely related to gender, environment, parents, and other factors. Therefore, how to increase the protective factors of children’s health behaviors and controlling the risk factors may be crucial to promoting the development of good health behaviors and improving the physical fitness of preschool children.