This study was a two-arm, parallel, randomized, controlled and open-label trial of 40 patients with moderate to severe obstructive sleep apnea. The patients were randomized to continuous positive airway pressure (CPAP) and CPAP + pulmonary rehabilitation (PR). The PR group underwent six weeks of 60-min twice-weekly individual PR programs. It was found that CPAP with a rehabilitation program improved functional ventilatory parameters and decreased BMI in patients with OSA. Hence, Treatment with CPAP combined with the PR program improved OSA patients to a greater extent than only CPAP and can be a useful part of comprehensive therapy in OSA.