Introduction: The rapid development of rs-fMRI in recent years can provide new scientific evidence of the plasticity of the child's brain. Objective: To reveal the effect of short-term moderate-intensity aerobic exercise on local consistency of brain function in children at rest, and to provide new evidence for elucidating the relationship between physical exercise and plasticity of children's brain. Methods: Using resting state functional magnetic resonance imaging (rs-fMRI) technology and local consistency (ReHo) analysis method to detect a 30-min short-term moderate-intensity aerobic exercise before and after children's brain function local consistency changes; using the Flanker task measurement Changes in children's executive function before and after exercise. Results: 1) A 30-min short-term moderate-intensity aerobic exercise made the children's bilateral posterior buckle back, left dorsolateral prefrontal lobe, left frontal medial gyrus, bilateral central posterior gyrus, left suboccipital gyrus, and tongue gyrus. 2) A 30-minute short-term moderate-intensity aerobic exercise improves children's executive function. 3) ReHo increases in bilateral posterior buckle gyrus, bilateral central parietal posterior gyrus, and left dorsal lateral prefrontal lobe are significantly associated with improved executive function. Conclusions: Short-term moderate-intensity aerobic exercise can improve brain plasticity and executive function by increasing local consistency of brain function in children at rest. Level of evidence II; Therapeutic studies - investigation of treatment results.