In this paper, upper extremity function to function better, but then the lack of stability and balance the body’s ability to attack a child lacking a stable position spastic diplegia both hands on the improved coordination of activities based on the upper extremity upper extremity function after applying the performance find out about what kind of changes which will. Study how the individual laboratory studies (single-subject experimental research design) were used for the design of the ABA. Session of the experiment consists of a total of 20 were three times baseline process, improved coordination of both hands based on the mediation process, who underwent upper extremity activities of 20 times, completing baseline regression process, the intervention process was measured three times in two weeks. Improve both hand coordination activities, based on the amount of five upper extremity (arm stretches to keep the bar and rings put, putting you release magnetic beads, putty, newspaper crease and tear) that perform the activities of, for each activity 5-7 minutes, twice a week were 10 weeks. For general information, medical records was obtained through pre-interviews, upper extremity function was assessed using the QUEST & Box and Block Test. In this study, the bilateral coordination training program affected children’s upper extremity function. Accordingly, it will be helpful to develop programs of using bilateral hands for children with spastic diplegia. Further study is needs to find various ways of promoting mobility and sociality.