Apert syndrome is a rare kind of craniosynostosis which is identified with fusion of cranial sutures during prematurity period and causes physical and intellectual disorders in younger ages. These patients may show symptoms of obstructive sleep apnea due to abnormal craniofacial shape. This article introduces a patient with Apert syndrome, with apnea symptoms, cyanosis, snoring, restlessness, night sweating, repeated sleep interrupts, and daytime irritability. Polysomnography was used due to a suspicious obstructive sleep apnea. The results were as follows: Arousal index: 3.27/h, RDI: 6.51/h, and Lowest oxygen saturation: 46%. CPAP with EPAP: 8cmH2o was used for the patient in sleeping time. Later test results and symptoms of the condition improved remarkably. Approximately 40% of patients with Apert syndrome have the symptoms of obstructive sleep apnea mainly because of mid face hypoplasia, but it can be related to changes of laryngopharynx, larynx, tracheobronchomalacia, and other abnormalities. If the condition is left untreated, obstructive sleep apnea can cause interruptive sleeping, repeated infections, delay in growth and cognition, and more importantly Cor pulmonale and sudden death in sleeping. Therefore, polysomnography must be considered and the patient should be under supervision.