Aim: Evaluating serum C-reactive protein level in patients with chronic obstructive pulmonary disease and its correlation with disease severity. Methods: A prospective study was conducted in the Department of Medicine, Darbhanga Medical College and Hospital, Laheriasarai, Darbhanga, Bihar, India for 13 months. 50 COPD patients and 50 asymptomatic individuals were selected as the control group. COPD patients underwent spirometry tests and the severity of disease was determined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. The main inclusion criteria for COPD patients were having symptoms or history of COPD with FEV1/FVC below 70% after using a bronchodilator. Results: In this study, 100 subjects were investigated (50 patients with COPD and 50 individuals as controls). In the COPD group, 29 subjects (58%) noted cigarette smoking during the study, 9 subjects (18%) reported cigarette smoking in the past, and 17subjects (34%) mentioned a history of baking. In the control group, 8 subjects (16%) noted cigarette smoking during the study; 4 subjects (8%) mentioned cigarette smoking in the past, and five subjects (10%) reported a history of baking. In this study, hsCRP was measured in 49 patients with COPD and 47 control subjects. The mean hsCRP was 7519±417 ng/mL in the COPD group and 2874±393 ng/mL in the control group. In the comparative study of the two groups using ttest, a significant difference was observed (p<0.001). The COPD group underwent spirometry and blood gas measurements, and then FEV1, FEV1%, FVC, and FEV1/FVC parameters were measured. The severity of the disease was determined by the GOLD criteria, where 16 subjects (32%) were GOLD II, 24 subjects (48%) were GOLD III, and 10 subjects (20%) were GOLD IV. There was no case of GOLD I found among the subjects because patients were hospitalized. Mean FEV1 was 1.25 L/s, mean FVC was 2.126 l, and mean FEV1/FVC was 58%. Conclusion: The findings of the present study demonstrated that plasma CRP is not only effective in the evaluation of inflammation in COPD, but also useful as a marker in monitoring inflammation during COPD treatment. CRP is decreased during treatment by inhaled corticosteroids.