[Purpose] The purpose of this study was to determine the effects of thorax correction exercises on flexed posture and chest function in older women with age-related hyperkyphosis. [Subjects and Methods] The study participants included 41 elderly women who were divided into a thorax correction exercise group (n = 20) and a control group (n = 21). Participants in the exercise group completed a specific exercise program that included breathing correction, thorax mobility, thorax stability, and thorax alignment training performed twice per week, 1 hour each session, for 8 weeks. Outcome measures included the flexed posture (thoracic kyphosis angle, forward head posture) and chest function (vital capacity, forced expiratory volume in a second, and chest expansion length). [Results] Participants in the thorax correction exercise group demonstrated significantly greater improvements in thoracic kyphosis angle, forward head, and chest expansion than those in the control group. [Conclusion] This study provides a promising exercise intervention that may improve flexed posture and chest function in older women with age-related hyperkyphosis.