Parkinson’s disease (PD) is a common neurodegenerative disease. Literature sources indicate the association of PD and mutations in the glucocerebrosidase A (GBA) gene. According to our study, the frequency of the two most common mutations in the GBA gene, N370S and L444P, is 1.85%. Mutation carriers have slower progression of motor symptoms, but are more likely to develop drug-induced motor fluctuations and dyskinesia. In carriers of GBA mutations, the severity of cognitive impairment corresponds to age-matched patients without mutations. Cognitive deficit in PD patients carrying GBA mutations primarily affects visual-spatial functions and often is associated with psychotic disorders and parasomnias syndrome. Other non-motor disorders in patients with GBA mutations do not differ from those in patients without mutations. In patients with PD and GBA mutations, a slower escalation of levodopa dose should be recommended because of the high risk of complications of therapy.