Objective The objective of this study is to evaluate the corneal endothelium in patients with chronic obstructive pulmonary disease (COPD) using a specular microscope. Methods The right eyes of 64 patients with a COPD diagnosis and 65 healthy individuals were evaluated. Cell density (CD) (cell/mm(2)), corneal thickness (CT) (mu), hexagonal cell ratio (%), and coefficient of variation (cell area standard deviation/mean cell area, mu m(2)) were analyzed by specular microscopy (SM). Results The CT was significantly reduced in the COPD group compared with the control group (P = 0.021). Moreover, a significant difference was found between the COPD group and the control group in terms of corneal endothelial CD (P = 0.011), hexagonal cell ratio (P = 0.008), and coefficient of variation (P = 0.012). Conclusion The corneal endothelial structure was significantly deteriorated in patients with COPD compared with the control group. SM is a valuable method that could be used in treatment and follow-up of corneal endothelium in patients with COPD.