Purpose: The aim of this study was to identify the effects of the lower trunk stabilization exercise using neurodevelopmental technique (NDT) on muscle activity in lumbar region and balance in the patients with hemiplegia. Methods: Fifteen participants were allocated in two groups: NDT group (n=8) or control group (n=7). NDT group performed NDT exercise program, while control group conducted walking exercise. Both interventions were given for 30 minutes a day, 3 times a week, for 5 weeks. To measure the muscle activity in rectus abdominis (RA), external oblique (EO) and internal oblique (IO), electromyography (EMG) was used. And, Timed-Up and Go (TUG) test and Berg-Balance Scale (BBS) were performed to assess balance before and after intervention. Results: NDT group showed a significant improvement of muscle activity in RA and EO, while control group did not show significant changes in three muscles. Also, there was a significant difference in muscle activity of RA and EO between two groups. In BBS and TUG test, participants in two groups showed significant improvements after intervention. Especially, significant difference was observed in TUG test between two groups (p<.05). Conclusion: This study demonstrated that NDT exercise is an effective intervention to improve the muscle activity in trunk region and to increase balance in patients with stroke. Thus, we suggested that NDT exercise program would be a treatment intervention in stroke rehabilitation.