Background: Chronic obstructive pulmonary disease (COPD) is a prominent worldwide cause of mortality and morbidity. Lung function, generally represented as forced expiratory volume in one second (FEV1), is used to classify diagnosis and disease progression. Exercise intolerance is a significant impairment in COPD patients. Their capacity to do daily activities and their quality of life are greatly impacted by the condition. Aim: This survey aimed to evaluate the ability of the five sit-to-stand (5STS), six-minute walk test (6MWT) and 4-meter gait speed (4MGS) test in predicting the severity of chronic obstructive pulmonary disease (COPD) exacerbations in stable COPD patients. Subjectts and methods: This prospective cohort study was performed at Chest Administrationt, Faculty of Medicine, Zagazig University and Ahmed Maher Teaching Hospital on 100 patients presenting with COPD. All selected participants were evaluated at baseline (T0) and after six months thorough medical history full, clinical examination, the classification of COPD exacerbation severity, ABG and spirometric PFT, the six-minute walking test, the five-repetition sit-to-stand test and the 4MGS test were performed. Results: This survey demonstrated that the 4MGS test and the 6MWT had extremely identical predictive destiny. While 5 STS showed the highest prediction values than 6MWT and 5STS. 5STS test and 4MGS test probably useful alternatives to the 6MWT for predicting severity of COPD exacerbation. Conclusion: through patients with stable COPD, physical tests as 6MWT, 5STS and 4MGS can predict the assumption, frequency and severity of acute exacerbation COPD .