To clarify the difference of brain atrophy between Parkinson s disease（PD）and progressive supranuclear palsy（PSP）, we compared the whole and regional brain volumes between the two disorders comprehensively. We conducted volumetric MRI examinations using Freesurfer software in 36 PD patients and 11 PSP patients to measure the volumes of whole brain and a total of 56 brain regions of interest. As a result, there was no significant difference in age, sex, duration, and severity between the two groups. however, the volumes of cerebral white matter, thalamus, pallidum, diencephalon, cerebellar white mater, and brainstem were significantly decreased and the volume of lateral ventricle, third ventricle, and fourth ventricle were significantly increased in the group of PSP compared to PD（p＜0.05）. in particular, the volumes of thalamus, diencephalon, cerebellar white matter, brainstem, third ventricle, and fourth ventricle showed the most significant differences between the two groups（p＜0.01）．