Objective To investigate the differences in the clinical features, polysomnographic characteristics and compliance with continuous positive airway pressure (CPAP) among elderly obstructive sleep apnea hypopnea syndrome (OSAHS) patients compared with those at young and middle ages. Methods A total of 220 PSG-diagnosed OSAHS patients in the Affiliated Hospital of Binzhou Medical College from January 2012 to July 2013 were subjected and retrospectively analyzed in this study. They were divided into the young group (aged 10 to 44 years, n＝89), middle-aged group (aged 45 to 59 years, n＝72) and elderly group (≥60 years old, n＝59). The clinica1 data, questionnaire, Epworth sleepiness scores and polysomnographic parameters were collected and compared. The 154 patients with apnea hypopnea index (AHI) ≥30 were followed up at 6 and 9 months, and 1 year. Totally 129 patients received CPAP. The application of noninvasive ventilator was also analyzed. Results The elderly patients had lower ratio of deep sleep at night (P＜0.05), and higher Epworth sleepiness scores (P＜0.01) when compared with young patients. They also had lower AHI than those weight-matched young patients (P＜0.05), but had severe sleep apnea at night (P＜0.05). The incidence of central sleep apnea was higher in the elderly group than in the other 2 groups (P＜0.05). The percentages of good compliance with CPAP at 6 months, 9 months and 1 year were 90%, 86% and 82% respectively in the elderly group, and were 89%, 87% and 79% respectively in middle-aged group, and 87%, 74% and 69% respectively in young group. The elderly patients had better compliance to CPAP than the other 2 groups(P＜0.05). Conclusion The elderly patients suffer more severe daily clinical manifestations, have worse sleep quality, and so, are more likely to have good compliance with CPAP.