Purpose Anxiety is a comorbidity that is not routinely addressed in patients with chronic obstructive lung disease (COPD) exacerbation in the emergency department (ED). Anxiety in patients with COPD exacerbation can be related with negative outcomes. The Generalized Anxiety Disorder 7 (GAD-7) score is an easy-to-use tool to determine anxiety. This study aimed to investigate the relationship between GAD-7 score and patient outcomes in patients with COPD exacerbation in the ED. Methods A prospective, cross-sectional study was conducted in a tertiary academic ED between July 2019 and January 2021. Patients admitted to the ED with COPD exacerbation were included. A GAD-7 score of >= 10 was defined as clinically significant anxiety. Negative outcomes were defined as a composite outcome that included recurrent ED visits, intensive care unit admission, and mortality. The relationship between clinically significant anxiety and negative outcomes within 30 days was determined. Results A total of 92 patients were assessed for eligibility and 80 were included in the study. Thirty-seven patients (46.3%) experienced negative outcomes. Although no significant difference was detected in median GAD-7 scores between patients with positive and negative outcomes, negative outcomes were significantly higher in patients who had a GAD-7 score of >= 10 (n = 25, p = 0.03). A sensitivity of 43.2%, specificity of 79.1%, positive likelihood ratio of 2.1 and negative likelihood ratio of 0.7 were determined for GAD-7 score in predicting negative outcome. Conclusion In patients with COPD exacerbation in the ED, a GAD-7 score of >= 10 was associated with 30-day negative outcomes.