PURPOSE: This study aimed to investigate the effect of active vibration exercise on trunk muscle activity, balance, and activities of daily living in patients with chronic stroke. METHODS: Twenty-four patients with chronic stroke were randomly assigned to an experimental (n=12) or a control (n=12) group. The experimental group performed an active vibration exercise workout for 20 minutes a day five times a week for 4 weeks using a flexi-bar. Trunk muscle activity was measured using surface electromyography. Balance was measured using the Berg balance scale. Activities of daily living were measured using the functional independence measure. RESULTS: The intragroup comparison showed significant differences in the rectus abdominis, internal oblique, and external oblique muscle activity values, Berg balance scale score, and functional independence measurement values in the experimental group. The intergroup comparison showed that differences in the rectus abdominis and internal oblique external oblique muscle values, Berg balance scale score, and functional independence measurement value for the experimental group were significantly related to those in the control group. CONCLUSION: Based on these results, this study proved that the active vibration exercise effectively improved trunk muscle activity, balance, and activities of daily living in patients with chronic stroke.