COPD is associated with several co–morbidities which substantially affect the clinical progression of the disease and patient’s survival. Studies have shown that lower pulmonary function increases the likelihood of cognitive impairment. In our study, the cognitive function was assessed by neuropsychological test battery using the Letter cancellation test, Trail making test A, Trail making test B, Digit span forward test and Digit span reverse test in the mild to moderate non–hypoxemic COPD patients. These tests are used for studying cognitive functions like executive function, immediate verbal memory, sustained attention, auditory attention and response speed. In Letter cancellation test greater time was taken by COPD cases to perform the same task than the healthy control group (p=0.003). Errors of omission was also more for the COPD cases (p= 0.025). The COPD cases took more time in Trail making test A and Trail making test B such that Significant difference was seen in the Trail making test A score (p=0.0395) and Trail making test B score (p= 0.0176). In the Reverse digit span test COPD case performed poorly in comparison to the control group (p= 0.002). Therefore it can be concluded from our study that even mild to moderate non–hypoxemic COPD is associated with cognitive decline apparent in different domains like attention, alertness, executive function and working memory.