Objective To explore the role of cerebral dopamine neurotrophic factor (CDNF) in the protection effect of Catalpol on the injured dopaminergic glial cells. Methods ①Mouse glial BV2 cells were randomly divided into control group, Catalpol group, 1-methyl-4-phenylpyridinium (MPP+) model group and MPP+ model+Catalpol group. The expression of CDNF mRNA in BV2 cells 0, 6, 24 and 48 h after treatment was detected by RT-PCR. ② BV2 cells were treated with 0.1, 1 and 10 μmol/L Catalpol respectively, MPP+ was added 24 h later, and the expression of CDNF protein was determined by Western blotting 48 h later. Normal cells were served as control group, and those without pretreatment with Catalpol were established as MPP+ model group. ③Control group, MPP+ model group, Catalpol group, anti-CDNF antibody group and Catalpol+ anti-CDNF antibody group were established, all groups were treated with MPP+ except control group, and the effect of Catalpol on dopamine uptake after CDNF antibody blockade was examined by [3H]-dopamine radiometry. Results ①Compared with control group, the expression of CDNF mRNA in Catalpol group and MPP+ model group was not significantly changed 0 to 72 h after administration of MPP+. However, the expression of CDNF mRNA in MPP+ model+ Catalpol group was significantly higher than that in MPP+ model group 48 h after administration of MPP+ （P<0.01）. ②The expression of CDNF protein in MPP+ model group was significantly lower than that in control group 48 h after administration of MPP+ （0.679±0.013 vs 1.009±0.015, P<0.001). The expression of CDNF protein in BV2 cells after pretreatment with 10 μmol/L Catalpol (0.812±0.011) was significantly higher than that in MPP+ model group （P<0.01）, while the expression of CDNF protein in BV2 cells after pretreatment with 0.1 and 1 μmol/L Catalpol was not significantly changed compared with MPP+ model group. ③The dopamine uptake in MPP+ model group was significantly lower than that in control group （63.5±2.5 vs 99.9±0.8, P<0.01）. The dopamine uptake in Catalpol group (87.2±2.4) was significantly higher than that in MPP+ model group （P<0.01）. The dopamine uptake in Catalpol+anti-CDNF antibody group (73.6±2.7) was significantly lower than that in Catalpol group （P<0.01）, while was higher than that in anti-CDNF antibody group （P<0.05）. Conclusion The neuroprotection effect of Catalpol against MPP+ toxicity may be associated with the upregulation of expression of CDNF mRNA and protein in BV2 cells.