The aim of this study was to determine the effect of walking exercise on oxygen saturation, dyspnea and happiness in COPD patients.In this study, 60 patients with mild and moderate COPD were included in the study according to the criteria defined in gold. (Global Strategy for the Diagnosis, Management, and Prevention of COPD) Patients who are in very heavy phase have not been taken. In the present study, a total of 60 patients, including 30 patients and 30 control subjects, who were diagnosed with COPD and who were accepted to participate in the study, were included in the study. Statistical analysis was performed using the t-test.In the experimental group with walking exercise, the mean of dyspnea scores decreased over time and in the control group, the increase was observed. The results of the experiment group showed that the happiness score average increased for 1 month in the first day. When the happiness scores of the control group are examined, there is a decrease in the happiness scores. When the oxygen saturation levels of the experimental group were examined, it was determined that the saturation levels of COPD patients were increasing. In the control group, the saturation level decreased for 1 month. While increasing the test group saturation level was determined, it was determined that the control group saturation level decreased.It was determined that walking exercise increased saturation and happiness scores in individuals diagnosed with COPD and decreased dyspnea scores.