Bacterial and viral infections are major causes of chronic obstructive pulmonary disease (COPD) exacerbations This study aimed to find out the frequency of typical and atypical pathogens in the etiology of COPD exacerbations, to evaluate the effect of these infections on the prognosis of the disease and their relationship with the history, clinical and laboratory findings of the patients. Typical agents were determined in 32.9% and atypical agents in in 37.1% of the patients. Atypical pathogens were more commonly isolated from younger patients with mild obstructive disease. There was no change in terms of response to therapy in typical and atypical pneumonia groups.