Objective:To explore the characteristics of sleep disorders in patients with Parkinson's disease (PD) and its correlation with homocysteine.Methods:Totally 75 PD patients hospitalized in the department of neurology from January 2017 to June 2021 were selected and divided into sleep disorder group ( n=39) and non-sleep disorder group ( n=36)according to polysomnography, Parkinson's disease sleep scale(PDSS) and Epworth sleepiness scale(ESS). The basic clinical data, hematological examination results, scale evaluation data and polysomnography monitoring data of the above patients were collected during hospitalization to analyze the sleep characteristics of patients with Parkinson's disease and its correlation with homocysteine.SPSS 26.0 statistical analysis software was used for t test, Mann-Whitney U test, Pearson analysis, Spearman analysis and multivariate Logistic analysis. Results:The sleep efficiency (56.82±19.07)%, N2 phase ratio(48.67±17.70)%, N3 phase ratio(9.20%(19.00%)) and the leg movement micro-arousal index(0(1.20)) in the sleep disorder group were lower than those in the non-sleep disorder group (sleep efficiency (82.15±5.55)%, N2 phase ratio(57.02±2.80)%, N3 phase ratio(20.01%(3.93%)), the leg movement micro-arousal index(1.15(1.80)). The differences were statistically significant ( t/ Z=-6.087, -2.905, -3.773, -3.683, all P<0.05). The proportion of AHI (0.90(14.60)), N1 stage (19.50%(15.70%)), and periodic limb index (0(24.80)) in sleep disorder group were higher than those in non-sleep disorder group (AHI (0.60(0.30)), N1 stage (12.15%(3.15%)), and periodic limb index (0(0)). The difference was statistically significant ( Z=2.154, 5.250, 3.559, all P<0.05). The homocysteine (15.80(3.90) μmol/L), NMSS-insomnia correlation score (3.00(5.00)), MDS-UPDRS-Ⅰ(7.00 (10.00)), MDS-UPDRS-Ⅲ (23.00 (16.00)) in the sleep disorder group were higher than those in the non-sleep disorder group (homocysteine (14.10 (4.20)μmol/L), NMSS-insomnia correlation score (0(1.00)), MDS-UPDRS-Ⅰ(3.00 (2.00)), MDS-UPDRS-Ⅲ (17.00 (4.00)), and the differences were statistically significant( Z=2.557, 4.487, 2.952, 2.180, all P<0.05). The NMSS-olfactory correlation scores (2.00(4.00)) and PDSS (99.00 (40.00)) were lower than those in the non-sleep disorder group (NMSS-olfactory correlation scores (4.50 (7.00)) and PDSS (122.00 (28.00)), and the differences were statistically significant ( Z=2.450, 4.126, both P<0.05). Hcy was positively correlated with sleep disorder in PD patients ( r=0.297, P<0.05). Binariate logistic regression analysis showed that elevated homocysteine level might be a risk factor for sleep disorder in PD patients ( β=0.193, OR=1.213, 95% CI=1.029-1.430). Conclusion:Parkinson's disease patients with sleep disorder have the characteristics of sleep structure disorder, often accompanied by more serious motor disorders, and the olfactory function impairment is relatively mild. Elevated homocysteine levels may be a risk factor for sleep disorder in Parkinson's disease.