INTRODUCTION: Chronic Obstructive Pulmonary Disease (COPD) is a progressive disease that develops due to inflammation in the airways. The aim of this study is to demonstrate the effectiveness of c-reactive protein/albumin ratio (CAR) as a 30-day mortality indicator in COPD patients admitted to ICU. MATERIAL AND METHODS: A total of 235 COPD patients with available data between January 2018 and December 2018 were included in this retrospective cohort study. Demographics, APACHE II, Charlson comorbidity index (CCI), SOFA score, CAR and outcomes were evaluated. RESULTS: 87 (37%) of the cases were female and 148 (63%) were male. Their ages ranged from 26 to 95 years, with an average of 70.9± 11.4. The non-survivors had significantly higher APACHE II, CCI, SOFA score, procalcitonin, creatinine, mechanical ventilation (MV) time, WBC, CRP and CAR compared to the survivors (p˂0.05). Albumin and prealbumin were significantly lower (p˂0.05) in non-survivors. In the univariate model; age, sepsis, inotropic support, APACHE II score, CCI, SOFA, procalcitonin, creatinine, MV time, WBC, CRP, albumin, prealbumin and CAR were observed to be significantly effective (p˂0.05) in predicting 30-day mortality. In the multivariate reduced model; inotropic support, SOFA, WBC and prealbumin value exhibited significant independent (p<0.05) effectiveness in predicting 30-day mortality. Albumin, CRP, CAR, APACHE II, SOFA and CCI value were observed to be significant in predicting mortality (p=0.000). CONCLUSIONS: In the study, the predictive power of APACHE II score, CCI, SOFA score, albumin and prealbumin values alone was found to be significantly higher than that of the CAR.