Abstract: OBJECTIVE To evaluate the inhibitory effect to periodic limb movement (PLMS) produced by propofol. METHODS 32 refractory insomniacs were observed in two different set-natural sleep group and propofol anesthesized group, monitored with EEG and polysomnography. RESULTS Both two groups had some patients who had periodic limb movements in sleep. There were no significant differences in incidence and periodic limb movement in sleep index between two groups. There was no abnormal change in patients’ EEG during periodic limb movement in sleep. CONCLUSION At clinical concentration, propofol does not produce the inhibitory effect to PLMS.