Objective To investigate the association between angiotensin (including angiotensin Ⅰ, angiotensin Ⅱ and angiotensin 1-7) and its converting enzyme (including angiotensin converting enzyme and angiotensin converting enzyme 2) and cognitive and motor impairments in Parkinson's Disease (PD). Methods The 200 patients' cognitive and motor functions were evaluated by collecting medical history, using Montreal cognitive assessment (MoCA), Mini-mental State Examination (MMSE) and other scales to assess cognitive function, and using the International Movement Disorders Association Parkinson's Disease Score scale to assess motor symptoms. Serum samples were collected, ACE, ACE2, AngI, AngII, Ang(1-7) and other indicators were detected by enzyme linked immunosorbent assay (ELISA) method, and PD cognitive and motor disorders were predicted by random forest model. Results Based on ACE, AngI, AngII, Ang1-7 and age, the predictive model of PD cognitive impairment on the accuracy of the validation set is 0.847, under ROC Curve and the coordinate axis of Area (AUC) value is 0.909. Based on the ACE, AngI and prediction model of PD dyskinesia Ang1-7 building on the validation set the AUC value is 0.618. Patients with early versus late dyskinesia showed statistically significant differences in ACE, AngI, AngII, and Ang1-7 levels regardless of the presence or absence of cognitive impairment. Conclusion The difference of renin-angiotensin system, especially ACE and AngI, in PD cognitive and motor disorders suggests that it may play a key role in the progression of PD disease. The random forest model performed well in predicting PD cognitive impairment and was helpful in early identification of PD patients with cognitive dysfunction. The potential of RAS components as PD biomarkers and therapeutic targets should be further investigated in the future to provide more comprehensive treatment strategies.