Objective:To study the characteristics and correlative factors of pulse oxygen saturation(SpO2) and exercise tolerance in the stable chronic obstructive pulmonary disease(COPD) during the 6-min walk test(6MWT) in order to provide a simple and effective method for objective assessment and management in COPD patients.Methods: The study included 58 stable COPD patients and 21 control subjects. General data,the modified Medical Research Council dyspnoea scale(mMRC),the COPD assessment test(CAT), pulmonary function parameters(such as FEV1%Pred?FVC%Pred?DLCO%Pred?DLCO/VA%Pred),6MWT-related parameters were collected. The study analyzed the differences in SpO2 and exercise tolerance indicators between groups,and their correlation with commonly used COPD assessment indicators.Results: COPD patients exhibited a decline in exercise SpO2 during the 6MWT, characterized by the decline in minimum SpO2(SpO2min) and mean SpO2(SpO2mean), an increase in the percentage of time with SpO2 below 88%, 90%, and 92% (T88, T90, T92) and desaturation area (DA) and the occurrence of exercise-induced desaturation(EID). There were differences in the 6-minute walk distance as a percentage of the predicted value (6MWD%Pred) and the desaturation distance ratio (DDR) between groups.SpO2mean,DA,DDR and 6MWD%Pred were all correlated with mMRC scores,FEV1%Pred,FVC%Pred and resting SpO2(SpO2rest).DDR was also related with DLCO%Pred and DLCO/VA%Pred. However, multiple linear regression analysis showed that only mMRC scores, DLCO%Pred, and SpO2rest were independently related to DDR. Conclusion: Continuous SpO2 monitoring during the 6MWT, with parameters such as SpO2mean, DA, DDR, and 6MWD%Pred, can effectively reflect the pulmonary function and symptoms of stable COPD patients. The assessment method is effective and can aid in the evaluation and management of COPD patients.