Abstract: Objective To observe the impact of obstructive sleep apnea hypopnea syndrome (OSAHS) upon glucose control and nocturnal glucose drifting in type 2diabetes patients. Methods Thirty one type 2 diabetes patients with OSAHS (group 1) and 18 type 2 diabetes patients without OSAHS (group 2) in our hospital were selected to conduct continuous glucose monitoring for 3 days and compare the nocturnal plasma glucose, fasting plasma glucose, 24 h plasma glucose, nocturnal mean amplitude of plasma glucose excursion (MAGE), day time MAGE, 24 h MAGE and GhBA1c between two groups. Results There was no significant differences in sex, age, duration of diabetes between 2 groups, but there was significance differences in body mass index, waist circumference and neck circumference (P0.05). Nocturnal MAGE and 24 h MAGE were significantly higher in group 1 than in group 2 after adjust of body mass index, waist circumference and neck circumference (P0.01) There were statistical differences on nocturnal plasma glucose, fasting plasma glucose, 24 h plasma glucose, 24 h MAGE and GhBA1c (P0.05) between 2 groups. Conclusion OSAHS may have an impact not only upon nocturnal plasma glucose, nocturnal MAGE, but also upon 24 h blood glucose and glucose drifting.