Aim: To investigate the developing status of physical stamina exercise in children with hyperkinetic syndrome, and analyze the differences between boys and girls. Methods: Totally 1 106 children (763 boys and 343 girls) with hyperkinetic syndrome, who were treated in the Department of Psychology and Intelligence, Children's Hospital affiliated to Capital Institute of Pediatrics between October 2001 and October 2004, were divided into 3, 4, 5 and 6-year-old group (n=220, 319, 280 and 287 respectively). Their physical stamina exercise was assessed with the standard of physical fitness measurement for 3 to 6-year-old children in Beijing city, including body height, body mass, pulse, 10 m × 2 shuttle running, standing long jump, softball throw, continuous long jump with both feet, walking on balance beam, continuous jump in a circle with single foot. Each item was scored as 5 grades: 5 points as excellent, 4 points as good, 3 points as pass, 2 points as below middle, 1 point as bad. The total score above 30 points as excellent, 27 to 29 as good, 21 to 26 points as pass, lower than 20 points as failed. Whether the items in the assessment of physical stamina exercise passed or not were observed, and gender differences were compared between boys and girls, percentage was used for statistical analysis. Results: Totally 1 106 children in all the age groups completed the examinations, and were involved in the analysis of results. 1 Gender differences in children with hyperkinetic syndrome: 68.99% (763/1 106) of them were boys, and 31.01% (343/1 106) were girls. In the 3, 4, 5 and 6-year-old groups, hyperkinetic syndrome was detected in 154, 225, 188 and 196 boys respectively, and in 66, 94, 92 and 91 girls respectively. 2 Results of assessment of physical stamina exercise in each age group: The total score of grade standard was pass and above in 45.66% (505/1 106) of the children, including 3.89% (43/1 106) were excellent, 7.32% (81/1 106) were good, and the rate of failure was 54.34% (601/1 106). The numbers of cases with pass and above were 60 boys and 24 girls in the 3-year-old group, 100 boys and 55 girls in the 4-year-old group, 91 boys and 44 girls in the 5-year-old group, 83 boys and 49 girls in the 6-year-old group; The numbers of cases with failure were 94 boys and 42 girls in the 3-year-old group, 125 boys and 39 girls in the 4-year-old group, 97 boys and 48 girls in the 5-year-old group, 113 boys and 42 girls in the 6-year-old group. 3 Gender difference of assessment of physical stamina exercise: 27.57% (305/1 106) of the children failed in all the items, 68.81% (761/1 106) failed in one or more items, only 3.6% (40/1 106) passed all the items, which were 29.5% (225/763), 66.6% (508/763) and 3.9% (30/763) in boys, and 23.3% (80/343), 73.7% (253/343) and 3.0% (10/343) in girls respectively. Conclusion: 1 In this study, there are more boys than girls with hyperkinetic syndrome, it also occurs more in boys than in girls in each age group. 2 More children with hyperkinetic syndrome fail in the physical stamina exercise, and most of them fail in one or more items.