Taken together, the data of this study confirmed the protective effects of exercise on endothelial dysfunction in obese children and adolescents and demonstrated that exercise training significantly reduces MALAT1 expression and increases miR-320a expression and that the MALAT1/miR-320a axis may be related with the alleviating effects of exercise on endothelial function in obese children and adolescents with obesity. This evidence concerns the gene MALAT1 and endothelial dysfunction.