Cardiovascular disease plays an important role regarding the morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). Sympathetic overactivity has been suggested to underpin the association between COPD and the development of cardiovascular disease. However, the pathophysiological basis by which sustained sympathetic overactivity affects cardiovascular function in patients with COPD is complex and incompletely understood. Different simple and more sophisticated measures of sympathetic activity, such as assessment of heart rate, blood pressure variability, and baroreflex sensitivity, provide information on the potential dysregulation of the autonomous nervous system. This review summarizes the findings from studies in animal models and humans on the potential relationship between COPD, sympathetic overactivity, and cardiovascular disease. There is preliminary evidence of sympathetic overactivity in COPD. However, direct evidence of a cause-effect relationship between sympathetic overactivity and cardiovascular disease from studies in COPD patients is lacking. Data from large cohorts of COPD patients and well-designed interventional studies looking at the relationship between COPD and autonomic nervous system function are urgently needed, hopefully leading to novel therapeutic and preventive approaches in the care of patients with COPD.