Objective: To explore the characteristics of short-term static balance of obese children by comparing the excursion of center of pressure (COP) of obese and non-obese children during the six kinds of circumstances. Methods: Characteristics of balance was examined using the 0.5m Footscan balance plate system (RSscan International, Belgium). Parameters on COP excursion of 47 obese children and 50 non-obese children were obtained when they were asked to stand for 10 seconds on both feet and single foot with eyes open and eyes closed, respectively. Results: The maximum displacement of COP in the anterior-posterior direction of the obese children was significantly greater than that of the non-obese children when children stood on both feet with eyes closed. When children stood on the left foot with eyes open, the sway velocity of the obese boys was significantly lower than that of the non-obese boys; the maximum displacement of COP in the medial-lateral direction of the obese boys was significantly lower than that of the non-obese boys and the maximum displacement of COP in the medial-lateral direction of the obese girls was significantly greater than that of the non-obese girls. The sway velocity of the boys was significantly greater than that of the girls when children stood on the left foot with eyes closed. Conclusions: In a short period of time, the static balance of obese children in the anterior-posterior direction is worse than that of non-obese children when standing on both feet with eyes closed. Obesity has different impacts on the static balance of different genders, the performance of static balance for obese boys are better than that of non-obese boys, the performance of static balance for obese girls are worse than that of non-obese girls when standing on left foot with eyes open. Girls have a better static balance performance than boys when standing on left foot with eyes closed. There were no significant differences for static balance performance between boys and girls in other circumstances. As static balance of children is affected by obesity and gender, it is suggested that different methods of losing weight should be considered for obese children of different genders.