This study was to test the immediate effects of foam roller and stretching exercises on hamstring muscle flexibility to identify more effective exercises for hamstring muscle flexibility and provide a basis for an exercise program. In addition, we would like to find out how an increase in hamstring flexibility affects the mobility of the lower back. In this study, 28 adult men and women enrolled at Daejeon University were selected as 14. Fourteen participants were randomly selected to join the Hamstring Foam Roller Group (HFG) and 14 subjects in the Hamstring Stretching Group (HSG) for assessment in the experiment on April 3, 2023. In this study, the Posterior Superior Iliac Spine (PSIS) will be palpated and marked in the locker room. Before the intervention, the SRT+Schober test, FFT+Schober test, and foam roller or stretching exercises will be assessed. After the intervention, the SRT+Schober test and FFT+Schober test are measured once more. the intervention method in this study involved two groups: one group used a foam roller, while the other group performed stretching exercises to relax the hamstring muscles. the application time for foam roller exercise is 3 sets of 90 seconds each, and for stretching exercise, it is 3 sets of 30 seconds each, with a 30-second rest period between each leg. The results indicated that both the Hamstring Foam Roller Group and the Hamstring Stretching Group showed a significant increase in SRT, SRT+Schober test, FFT, and FFT+Schober test after the intervention compared to before the intervention. However, there was no significant difference between the groups. The conclusion of this study suggests that this data can serve as a fundamental basis for an exercise program that can be widely utilized, not only by typical adults, but also by athletes aiming to improve performance, and by elderly individuals in the community seeking to prevent falls.