Background: Chronic obstructive pulmonary disease (COPD) is a disease characterized by a progressive airflow limitation. Soluble urokinase-type plasminogen activator receptor (suPAR) is released from the membrane-bound plasminogen activator, and is positively correlated with the activation of immune system. Aims: Release of inflammatory mediators is increased in chronic obstructive pulmonary disease (COPD), particularly during exacerbations. The objective of this study was to compare plasma levels of suPAR and serum levels of C-reactive protein (CRP) during exacerbation and stable periods in patients with COPD. Study Design: Prospective clinical study. Methods: The patients with COPD were divided into 3 groups for evaluations: those with stable COPD [SCOPD] (n= 54), pre-treatment acute exacerbation COPD [AECOPD] (n= 53), and post-treatment AECOPD (n= 52). Plasma suPARand serum CRP levels were assessed for each patient. Results: Whereas the increased serum CRP levels of the participants were 54.82±56.63 mg/l during acute exacerbation period, during the stable period it was 5.02±6.31 mg/l and statistically significant (p= 0.0001). The suPAR level was 1.28±0.52ng/ml during the acute exacerbation period vs.1.21±0.59ng/ml during the stable period, without a difference (p= 0.49). There was a statistically significant decrease in the CRP serum levels; yet, although not statistically significant a remarkable decrease was seen in the suPAR levels obtained before and after the management of exacerbations (p= 0.001 and p= 0.06 respectively). Conclusion: These results support the idea that suPAR, a novel biomarker, might be an important indicator if verified with further prospective studies in evaluating COPD exacerbations and treatment response like CRP used for decades.