This study examined 4- and 5-year-old children to elucidate effects of playing tag as an intervention for endurance ability in kindergarten children. Two classes in each age group were designated as an intervention group and a control group. Six highly active tag programs were chosen, three tag playing sessions, 70-80 s each, were conducted five times in each intervention. A 20 m shuttle run was used pre-intervention and post-intervention as a test. The test for 20 m shuttle run performance after the 4-week intervention revealed no significant difference between groups of four-year-old children. However, significant improvement was found for the intervention group of five-year-old children. Results suggest that exercise intensities in five-year-old children were higher than in four-year-old children.