Parkinson''s disease (PD) is a common clinical neurodegenerative disease second to Alzheimer''s disease. Substantia nigra substantia nigra hyperechogenicity(SN+) found by transcranial sonography(TCS) is an important examination for the diagnosis and differential diagnosis of PD. However, the cause of SN+ is not clear, its correlation with symptom severity is still controversial, and its relationship with clinical classification and staging has not been determined. TCS can also identify several motor and affective disorders through the exploration of midbrain raphe and basal ganglia, and more and more studies are expanding the use of TCS in clinical practice.