Nocturnal sleep disorders are one of the most important non-motor manifestations of Parkinson’s disease (PD). The clinical significance of sleep disorders in PD is determined by their frequency (up to 88%) and negative impact on quality of life in patients. The paper presents the clinical spectrum of sleep disorders in PD, current approaches to their diagnosis. It discusses the multifactorial nature of the pathophysiology of these disorders. Current views on the relationship of sleep disorders to the neurodegeneration of brain structures involved in the regulation of sleep and wakefulness, to circadian disorders and therapy are depicted. On the basis of the heterogeneity of sleep disorders in PD, a differentiated approach to their treatment is substantiated having regard to the nature of dyssomnic disorders and leading pathophysiological factors. Emphasis is focused on the basic principles of differentiated therapy for sleep disorders in PD in relation to the degree of nocturnal motor symptoms of the disease. There are clinical findings indicating an improvement in the characteristics of nocturnal sleep and a reduction in nocturnal sleep disorders during therapy with long- acting ropinirole, a D2-receptor agonist. Approaches to the pharmacotherapy of non-motor disorders of PD, which worsen nocturnal sleep, are depicted. Non-drug therapies for sleep disorders and their efficiency in patients with PD are discussed.