Objective : The purpose of this study is to evaluate the effect of task-oriented mirror therapy involve visual illusion on upper extremity functions in stroke patients. Method : We divided into two groups that task-oriented mirror therapeutic exercise program include visual illusion and not include. In order to determine the change in upper extremity function, Box & Block Test and Line-bisection Test was evaluated each time period. Result : The result of this study that we found out that all participation's upper extremity function had been improved during the intervention and sustained during baseline regression. Applying mirror therapy program include visual illusion group more improved trend line during the intervention, visual illusion group, it had been shown there are higher difference between visual illusion group and non-visual illusion group in upper extremity functions. Conclusion : It is thoughtful that task-oriented mirror therapy could help for stroke. It might be more effectiveness to apply who have exercise program include visual illusion.