Purpose: This study demonstrated a postural alignment exercise as conservative management strategy for a woman with excessive thoracic kyphosis presenting decreased chest function, and reports its results. Methods: A 21-year-old woman with thoracic kyphosis presenting limited chest function. The exercise program underwent for 30 min in the intervention phase, which consisted of exercises to improve the strength of back extensor and to stretch anterior chest region. Outcome measures comprised the severity of thoracic kyphosis and chest function (vital capacity [VC], forced expiratory volume in a second [FEV1], and chest expansion length). Results: The thoracic kyphotic angle decreased by 23.6% ($9.38^{circ}$) and 25.4% ($10.58^{circ}$) in the intervention and follow-up phases respectively. Also, chest function was improved in the intervention (VC: 3.7% [$0.10{ell}$], FEV1: 17.1% [$0.39{ell}$], and chest expansion length: 17.1% [0.96 cm]), and the improvement was maintained during the follow-up phase (VC: 4.8% [$0.13{ell}$], FEV1: 17.1% [$0.39{ell}$], and chest expansion length: 64.3% [1.81 cm]). Conclusion: These findings suggest that the postural alignment exercise was favorable for improving chest function of a woman with thoracic kyphosis.