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Aim: To develop a cell-based model by stable transfection of SH-SY5Y with mu-tant A53T human α-synuclein, recapitulating neurotoxicity of α-synuclein overexpression. Methods: The overexpression of mutant α-synuclein was ana-lyzed by West blotting, immunocytochemistry, and RT-PCR. Cell viability was processed when treated with different concentrations of 1-methyl-4-phenyl-pyridinium (MPP+) and exogenous dopamine (DA) for 24, 48, and 72 h by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Early apoptosis and late apoptosis/necrosis were analyzed by flow cytometry using Annexin V and propidium iodide double staining, respectively. DNA was isolated and applied to agarose gel for electrophoresis; the typical DNA ladder repre-sented severe apoptosis. We also used this model to screen 99 compounds with therapeutic potential by MTT assay. Results: One of the stably-transfected clones overexpressed exogenous genes on both the protein level and the transcriptive level. Significant differences in cytotoxicity were found between the pcDNA3.1(+) group and the pcDNA3.1(+)-hmα-synuclein group in the presence of the same concentration of MPP+ and DA within the same incubation time. The level of either early apoptosis or late apoptosis/necrosis was remarkably increased in transfected cells compared with the control after treatment with 100 μmol/L MPP+ for 24 h. In addition, the presence of the typical DNA ladder was ob-served in the pcDNA3.1 (+)-hmα-synuclein group when treated with 200 μmol/L MPF+ for 48 h. After the screening experiment, 12 of the 99 compounds were found to decrease DA-induced cytotoxicity on cell viability. Conclusion: We estab-lished a cell-based model which is useful for studying the function of α-synuclein and screening compounds with therapeutic potential. In addition, it was identi-fied that cells overexpressing A53T mutant α-synuclein were significantly vulner-able against MPP+ or dopamine exposures.