Abstract： Objective To determine the reliability and validity of the COPD assessment test (CAT)Chinese version in patients with chronic obstructive pulmonary disease ( COPD ), and to study its value in evaluating quality of life in Chinese patients.Methods One hundred and thirty-five patients with COPD in stable condition from Peking Union Medical College Hospital were assessed by interview with CAT Chinese version,and underwent pulmonary function test on the same day.The validity was documented by performing correlation analysis, and Pearson' s correlation coefficients were calculated.The stages of COPD determined by CAT score and lung function were compared to observe the value of CAT in determining disease severity.Results Cronbach' s alpha of CAT Chinese version was 0.805.CAT score increased with the severity of the disease, and was negatively correlated to FEV1 % of predicted ( r = - 0.567, P ＜ 0.01 ).CAT score varied significantly in patients ( 10 ± 5, 16 ± 6, 21 ± 7 and 23 ± 6 ), with different severity of COPD ( x2 =48.437, P ＜0.01 ).There was a high degree of consistency between the stages of COPD determined by CAT score and lung function.Conclusions The Chinese version of the CAT had good internal consistency reliability and validity, and can be used to assess the quality of life for Chinese COPD patients.It provided a simple, valid and standardized measurement of COPD health status.