OBJECTIVE: This study aimed to investigate the utility of assessing motor symptoms, olfactory test and transcranial ultrasonography in diagnosis of Parkinsons disease (PD).METHODS: Fifty PD patients and fifty age-and gender-matched non-PD individuals as control group were recruited.Unified Parkinsons Disease Rating ScaleⅢ (UPDRS Ⅲ), T&T olfactometry and transcranial ultrasonography were applied respectively to assess motor asymmetry, olfactory function and substantia nigra (SN) echogenicity.Hyposmia and SN hyperechogenicity (SN+)s influencing factors were analyzed, and three assessments and the combineds sensitivity, specificity and positive predictive value for diagnosis of PD were calculated respectively.