Acromegaly results from the long-term hypersecretion of growth hormone (GH) and elevation of levels of its peripheral mediator insulin-like growth factor-1.Acromegaly is known to signicantly increase mortality rate. Cardiovascular diseases are the most common causes of death in acromegalic patients. Moreover acromegalic patients with cardiac hypertrophy have a decreased cardiopulmonary performance during exercise as compared to normal subjects. The aim of our study was to assess pulmonary functions and the cardiopulmonary response to exercise in acromegaly. Ten patients who were followed by endocrinology department outpatients clinic were enrolled to study. Disease activity was evaluated by growth hormone levels. All the patients were evaluated by the body measurements, pulmonary function tests, body plethismography results. CPETs of the patients were performed. Ten patients(2 Male, 8 Female) were enrolled to study. Two of them were new diagnosed active acromegaly and 8 of them were under treatment. Mean age was 37.8± 10,5. Two patients were evaluated for pulmonary function for the study before treatment while they were active disease duration. All the patient‘s FEV/FVC ratio were greater than %70 (Mean: 80.7±8,8). All the TLC values of the patients were nearly upper limit of normal.When the CPETs were performed, 2 patients whose active disease test were ended because of the early arrhythmia and hipertension. None of the patients could reach maximal exercise capacity because of the muscular fatique and all the patients VO2 max were reduced.Non invasive CPET results were compatible with poor effort.