Objective：To investigate the effects of nasal continualpositive airway pressure（NCPAP） on adiponectin and mean arterial pressure（MAP） in patients with obstructive sleep apnea hypopnea syndrome（OSAHS）. Methods：The effects of NCPAP therapy on serum adiponectin and MAP levels were observed in 23 patients with moderate or severe OSAHS before and on the 3rd, 7th,14th day of NCPAP treatment. Results：Adiponectin levels were significantly higher in patients 14 days after treatment with NCPAP（P < 0.01）. MAP level was significantly lower in patients on 14th day of NCPAP treatment（P < 0.01）. Conclusion：The results suggest OSAHS could cause hypoadiponectinemia, which might be involved in the pathogenesis of hypertension in OSAHS patients and might be reversed by NCPAP therapy.