ObjectiveAnalyzing change of sleep construction and its clinical significance in patients with epilepsy Methods The 24h ambulatory EEGs(AEEG) during interictal were monitored in 58 patients with epilepsy and control group (58 normal persons). Results 1. The sleep period tiae and time of REM (rapid eye movement sleep)were no marked difference between the epilepsy and control groups, 479.98±67. 4 min in epilepsy, 496. 33±57.62 min in control. 2. In coaparison with those of the control, the epilepsy group showed that the NREM ( non rapid eye movement sleep) stage Ⅰ- Ⅱ was longer(68±6.61%and 56.33±7.01%respectively), the NREM stage Ⅲ-Ⅳ was shorter (7. 03±5. 41%and 18.42±6. 94%respectively) . There were a significance difference between the two groups (P＜0。 01) . 3. The arousal times (268 times) in epilepsy were higher than those (15 times) of the control (P＜0.01). 4. The results of correlated analysis showed that there was a significant positive correlation between the arousal times and the frequency of epileptifora discharges in epilepsy (r=0.639, P＜0. 01). 5. The sleep spindles in 12 patients (21%) decreased and asymmetrical, normal in the control. Conclusion: There were the sleep disorders in patients with epilepsy . The epileptic activity during interictal can obvious influences on sleep quality in patients with epilepsy.