The purpose of this study was to investigate the effectiveness of object control activities on the eye-hand coordination and object control skill ability of children with Down syndrome. As the subject of this study, elementary school boys(n=16) with trisomy 21 Down syndrome were selected. The experiment was conducted for 16 weeks, 2 sessions per week, and 90 minutes per session. In addition, a test on eye-hand coordination and a test on five object control skills((rolling underhand, overhand throw, catch, two-hand strike, stationary bounce) were conducted before and after the program effectuated. The data were analyzed by ANCOVA for identifying difference between the experiment group and control group. The significant level was set at a=.05 to verify the hypothesis. The results of this study were drawn as follows: It could be seen that after the object control activities was effectuated for 16 weeks, there was statistically significant positively effected the enhancement of eye-hand coordination and object control skill ability of children with Down syndrome. In conclusion, the object control activities positively effected the enhancement of eye-hand coordination and object control skill ability of children with Down syndrome.