Objective：To investigate brain changes of cortical gray volume and function between dementia with Lewy body（DLB）and Parkinson’s disease（PD）. Methods：A total of 16 DLB patients，20 PD patients and 20 well-matched healthy controls were scanned with T1 structure and resting-state functional magnetic resonance imaging for regional homogeneity（ReHo） and gray matter volume（GMV） analyses. The Mini mental state examination（MMSE），Montreal cognitive assessment（MoCA）and unified Parkinson’s disease rating scale-Ⅲ（UPDRS-Ⅲ）were performed to assess the clinical symptom，as well as its correlations with ReHo and GMV. Results：① Compared with the controls，the DLB groups showed higher ReHo in left cerebellum anterior lobe，bilateral calcarine，bilateral caudate，and lower ReHo in left middle frontal gyrus，while PD patients had increased ReHo in right superior temporal gyrus，right supra marginal. Compared with the PD patients，the DLB patients had significantly increased ReHo in bilateral caudate，as well as decreased ReHo in right supra marginal，left inferior frontal gyrus.② Compared with the controls，the DLB patients show reduced GMV in bilateral caudate，right temporal lobe；Compared with the PD patients，the DLB patients show reduced GMV in right caudate，right temporal lobe.③ There are significantly negative correlation between ReHo and UPDRS-Ⅲ scores in bilateral caudate in DLB patients. Conclusion：The structural and functional changes in brain of DLB patients may be related to disease’s physiopathologic mechanism.