COPD is an airway flow restriction that is not responded or partially responded to bronchodilators. In this study, we compared the newly defined COPD assessment test (CAT) with other tests defined for the same purpose.COPD patients presented to outpatient and inpatient clinic of Pulmonary Department were enrolled to the study. Age, file numbers, phone numbers, disease period, COPD stage, smoking and environmental biomass exposure, COPD exacerbation and hospitalization history in the past 1 year period and 3 months period after the test and co-morbidities of the patients were recorded. After these test, face to face m MRC, SGRQ and CAT were doneForty eight male (92,3%) and 4 female (7,7%) patients were enrolled to the study. When we evaluate the CAT score of the patients; the score of inpatient cases were significantly higher than cases of outpatient clinic (29,73±8,37 versus 17,2± 6,80 and p<0,01). When we compared the mean CAT scores of the patients and other dyspnea scales, significant difference was found with mMRC stage 4 and stage 5. In SGRQ total score significant difference was observed between cases took a score under 60 and a score above 60. Positive significant correlation was found between CAT score, SGRQ division and total scores and with Borg and mMRC scale (p<0,01).CAT is a easy, short, understandable test to show the characteristic and complex structure of COPD in every stage and will provide optimum evaluation by providing the communication between the clinician and patient in daily practice.