BACKGROUND: Sleep disturbance (SD), parasomnia and excessive daytime sleepiness (EDS) are commonly reported in Parkinson disease (PD). But frequencies and etiological factors are not congruent in different studies. METHODS: We studied those patients who had visited our clinic and had been diagnosed as PD using a structured questionnaire. Disease severity was graded according to Hoehn and Yahr stage into 8 stages. Drug history of the patients is reviewed by medical records. SD is defined to be present when one complains of poor sleep regardless of sleep duration. We define sleep benefiter as those who are 'best' and 'on' in the morning. If one has 10 or more scores on the Epworth sleepiness scale, we regard him/her as having EDS. RESULTS: One hundred PD patients are recruited. Thirty-eight of them complain of sleep disturbance. The patients with SD need longer time to get into sleep, and have shorter sleep duration than those without SD. The average number of sleep fragmentation is higher in SD group. Vivid dreams are the most common parasomnia. Sleep benefiters are 61%. They have less amount of levodopa equivalent dose than non-sleep benefiter. Those with EDS have shorter sleep duration. And there are more snorers in them. CONCLUSIONS: We can confirm that SD, parasomnia and sleep benefit is commonly observed in PD patients.