Abstract: Objective: To investigate the application of diffusion tensor imaging (DTI) and susceptibility weighted imaging (SWI) in the changes of substantia nigra in patients with early primary Parkinson's disease. Methods: Conventional sequence, DTI, and SWI scans were performed on 13 patients with early primary Parkinson's disease and 13 volunteers as controls using a 3 T magnetic resonance imaging system. The FA and ADC values of the substantia nigra of the two groups and the size of the substantia nigra pars compacta were measured. Results: The FA values of bilateral substantia nigra were reduced in the PD group compared with the control group, the difference was statistically meaning (P<0.05). There was no significant difference in the ADC values of the substantia nigra between the two groups (P>0.05). The size of the substantia nigra pars compact in the PD group was smaller than that in the control group, the difference was statistically meaning (P<0.05). Conclusions: The FA value of the substantia nigra and the size of the substantia nigra pars compacta contribute to the early diagnosis of PD. DTI and SWI have a synergistic effect and may provide valuable clues for the early diagnosis of PD.