Objectives: To determine the frequency of major sleep disorders in patients with Parkinson’s disease (PD), diagnosed according to the third international classification of sleep disorders, and assess the relationship of those disorders with the quality of life. Methods: A cross-sectional study was performed involving 88 consecutive patients with PD from outpatient clinic. Participants were subjected to clinical interviews, assessment using standardized scales (Epworth Sleepiness Scale, PD Questionnaire, Pittsburgh sleep quality index (PSQI) and, for individuals with a diagnosis of RLS/WED, International RLS/WED grading scale), and video-polysomnography. Results: We observed sleep disorders in 96.5% of the participants, with REM-sleep behavior disorder found in 62.5%, obstructive sleep apnea in 62.5%, insomnia in 55.7%, and restless legs syndrome in 28.4%. We observed a correlation between health-related quality of life with the PSQI and the Epworth sleepiness scale. Conclusion: Patients with PD have a high prevalence of sleep disorders. The quality of sleep and excessive daytime sleepiness significantly affect the quality of life in these individuals.