Purpose The of this study was to investigate the influence of Lower-Trunk Stability Strengthening Exercise on balance in Stroke Patients Method 14 stroke patients participated in this study. These patients were divided into two groups( a core stability group and a control group). There were 7 subjects in each groups They participated in Lower-Trunk Stability Strengthening Exercise for 3 weeks. Timed Up and Go Test(TUG) and Messen Trairuieren Dokumentieren(MTD) Systems for balance were measured and compared before and after the treatment Result Lower-trunk stability strengthening exercise on stroke patients for three weeks was effective for the treatment to improve balance of the core stability group. Conclusion The effort to apply the lower-trunk stability strengthening exercise for stroke patients is thought to be necessary.