Objective To study the neurotoxicity induced by rotenone to the primary cultured ventral mesencephalic dopaminergic neurons. Methods SD rat ventral mesencephalic neurocytes were cultured and identified by tyrosine hydroxylase (TH) and glial fibrillary acid protein (GFAP). Immunohistochemistry and morphological observation were used to evaluate the toxicity of rotenone to the dopaminergic neurons and astroglia. Results After 24 h of exposure to rotenone at 0.10 and 1.00 μmol/L, the number of surviving dopaminergic neurons significantly decreased. The number of surviving astrocytes significantly decreased treated with 1.00 μmol/L. Exposed to 0.10 μmol/L rotenone, the morphological change of the dopaminergic neurons was seen, the area of cell body decreased significantly. Conclusion The dopaminergic neurons is more susceptible to the neurotoxicity of rotenone.