[Purpose] The aim of this study was to examine the initial effects of chest expansion resistance exercise (CERE) applied to chronic stroke patients on their pulmonary functions, chest expansion, and functional gait ability. [Subjects] Forty chronic stroke patients without any respiration-related rehabilitation program experience (21 men and 19 women; times elapsed since occurrence of stroke: 21.8 ± 5.3 months) were randomly and equally allocated to a CERE group (experimental group) and a control group. [Methods] An ordinary stroke rehabilitation program was performed on the subjects. While the experimental group received a CERE intervention, the control group performed passive range of motion exercise with automatic instruments. [Results] The CERE group’s chest expansion significantly increased after the intervention, whereas the control group did not see any significant difference. As regards VC (vital capacity), FVC (forced vital capacity), and FEV₁ (forced expiratory volume in one second), there were no significant changes in either the CERE or control group. In the 10MTWT (10-meter timed walking test), there were no significant changes in either group, but in the 6MWT (6-minute walk test), while there were no significant differences in the control group, the CERE group saw significant changes. [Conclusion] The results of application of CERE to chronic stroke patients demonstrated the importance of respiratory exercise in an approach to stroke rehabilitation treatment intervention and the need to add respiratory exercise to a rehabilitation intervention program.