Abstract: Objective:To investigate the relationships between serum uric acid(UA) level,and different motor subtypes and clinical stage of Parkinson's disease(PD).Methods:PD patients and age and sex-matched healthy people were divided into the PD group(n=50)and control group(HC group,n=50),respectively.The PD group were subdivided into TD group(tremor-dominant) and PIGD group(postural instability and gait difficulty-dominant) according to the dyskinesia symptom.The disease severity was evaluated by Hoehn-Yahr(H-Y) scale,which could evaluated for early-stage(H-Y<3) and advanced-stage(H-Y≥3).The serum levels of UA and creatinine(Cr) in all cases were measured.Results:The serum UA level in PD group was lower than that in HC group(P<0.01).Compared with the TD group,the serum level of UA in PIGD group was significantly decreased(P<0.05).The serum level of UA in middle and advanced PD patients was lower that in early patients(P<0.01).The difference of the serum level of Cr between all cases was not statistically significant(P>0.05).Conclusions:The UA change may be involved in the pathogenesis of different motor subtypes of PD,which may be a potential useful biomarker in predicting risk,and diagnosing the severity and motor subtype of PD.