OBJECTIVES: We aimed to evaluate the efficacy of biofeedback-assisted autogenic training for chronic tension-type headache, and to determine the relationship among the changes in electromyography (EMG) activity, headache activity, and mood states according to the psychophysiological treatment. METHODS: Chronic tension-type headache patients aged from 20 to 40 years (n=35) were randomized to the treatment group receiving biofeedback-assisted autogenic training (8 sessions) or the monitoring-only control group. EMG activities, headache index, and various psychological variables were examined. RESULTS: We found greater treatment response rate (> or =50% reduction in headache index) in patients with biofeedbackassisted autogenic training than in the monitoring group (61% vs. 18%; chi-square=6.882, df=1, p=0.01). There were no significant changes in the mean values of the pretreatment EMG activities across the sessions in either group (all p's>0.1). Mood states including anxiety and depression improved over time in the both groups, with the improvements being more prominent in the treatment group. Moreover, the reduction in depression level predicted treatment outcome in terms of headache index (95% confidence interval: 0.272-0.966, p=0.039). CONCLUSION: These results show that biofeedback-assisted autogenic training is effective for the treatment of chronic tension-type headache in a Korean population. Changes in mood states may be closely associated with the clinical outcome in the treatment of chronic tension-type headache using biofeedback-assisted autogenic training.