Parkinsons disease (PD) is a chronic neurodegenerative disease. The pathogenesis of PD is the misfolding and accumulation of the alpha-synuclein protein leading to degeneration and death of dopaminergic neurons in the Substantia nigra. This study focuses on the transmissibility of phosphorylated -synuclein in the brain of PD model mice. In this study, DAT-IRES-Cre+/-/LSL-SNCA-GFP+/- mice was used as a model, and experimental techniques including frozen section of mouse brain, immunohistochemical staining, and confocal microscopy were used to investigate the transmission of -synuclein as well as Lewy bodies, which are abnormal aggregates of -synuclein, in the mouse brain. We conclude that phosphorylated -synuclein (pSyn) can propagate from the dorsal striatum to the Substantia Nigra Pars Compacta (SNc) through the dopaminergic pathway, resulting in the formation of Lewy bodies in dopaminergic neurons in the SNc, causing neuronal death and thus leading to the pathogenesis of Parkinsons disease.