Objective: To analyze the childhood blood pressure (BP) trajectory and its relationship with overweight and obesity, to provide evidence regarding prevention and control of childhood elevated BP. Methods: A total of 1 177 children who participated in five surveys of Zigong school based cardiometabolic risks survey. Elevated BP was defined by using National BP reference for Chinese children. Groupbased trajectory model was used to identify distinct BP trajectories. Logistic models were conducted to investigate the association of number of overweight/obesity across surveys with BP trajectory. Results: In the five consecutive waves, the corresponding prevalence of elevated BP was 1.9%, 6.6%, 7.0%, 12.5% and 11.2%. Childhood BP trajectory were classified into constant low and high increasing risk of elevated BP groups. The risk of elevated BP increased at a steady rate with age in constant low risk of elevated BP groups, while the risk of elevated BP increased dramatically with age in high increasing risk of elevated BP groups. Logistic regression analysis showed that those with increasing number of occurrence of overweight/obesity tended to be classified into high increasing risk of elevated BP group( OR=1.34, 95%CI=1.17-1.53, P <0.01). Conclusion Blood pressure trajectory during childhood varies. The risk of elevated BP increased dramatically with age in overweight and obese children. Attention should be paid to the BP trajectory of overweight and obese children to prevent elevated BP.