To investigate the neuroprotective effect and mechanism of mangiferin on SH-SY5Y cell injury induced by H2O2 in the cellular model of Parkinson’s disease. Methods: SH-SY5Y cells were divided into the control group, model group, and high, medium, and low dose mangiferin groups. The cells were incubated with PBS in the control group, with 100 μmol/L H2O2 for 4 h in the model group, and pretreated with mangiferin (25, 50, and 100 nmol/L) for 4 h then incubated with 200 μmol/L H2O2 for 4 h in the high, medium, and low dose mangiferin groups. The MTT assay was used to detect the survival rate and Western-blot to detect the expression levels of DUSP6 and ERK1/2 in SH-SY5Y cells. Reagent test kits were used to measure the level of lactate dehydrogenase (LDH) in the medium and the level of malondialdehyde (MDA) and superoxide dismutase (SOD) in the cells. Results: Compared with the control group，the model group showed a significantly decreased cell survival rate, increased LDA and MDA levels, and decreased SOD levels. Compared with the model group, the high, medium, and low dose mangiferin groups showed significantly increased cell survival rates, decreased LDH and MDA levels, and increased SOD levels. Compared with the control group, the model group displayed increased DUSP6 expression and decreased p-ERK1/2 expression. Compared with the model group, the high, medium, and low dose mangiferin groups displayed decreased DUSP6 expression and increased p-ERK1/2 expression. The expression of Nrf2 and HO-1 was reduced and that of Keap1 increased in the model group compared to the control group. The expression of Nrf2 and HO-1 was increased and that of Keap1 reduced in the high, medium, and low dose mangiferin groups compared to the model group. Conclusion: Mangiferin confers a significant protective effect against the injury induced by H2O2 in SH-SY5Y cells, and the mechanism may be related to the inhibition of oxidative stress via the DUSP6/ERK1/2 and Keap1/Nrf2 pathway.