PURPOSE: This study was conducted in chronic hemiplegic patients to examine the effect of the training of the ipsilateral arm that is identical to the model performing movements and the training of the contralateral arm on the function of the arm. METHODS: The subjects were participated total 2 patients(the subject 1 with left hemiplegia and the subject 2 with right hemiplegia). The study was conducted for 4 weeks. The action observation training were repeated 10 times in 10 days during intervention period. The evaluation of the arm function such as BBT, MFT and MAL in the each subject were examined 5 times in the baseline period, 10 times during the intervention period and 5 times during the baseline regression period. RESULTS: The results of the evaluation in each subject were presented as mean values and video graphs. The arm function of the 2 subjects were improved during the intervention period in comparison with the baseline period, and the improvement was maintained even during the regression baseline period. In addition, there were large variation ratio of BBT and MAL (AOU, QOM) in comparison with subject 1. CONCLUSION: According to the results, the action observation training was more effective in improving upper limb function of stroke patients who imitate the performed behavior of paralyed parts on the same side.