To clarify the antioxidative effect of Crataegi Fructus (CF) extract on the cytotoxicity induced by FeSO4, hair dye component, antioxidative effects such as DPPH-radical scavenging activity and lactate dehydrogenase (LDH) activity as well as cell viability by XTT assay were performed. Cell viability and LDH activity were assessed after NIH3T3 fibroblasts were cultured in media containing various concentrations of FeSO4. And also, the effect of antioxidant, vitamin E on FeSO4-induced cytotoxicity was evaluated. For the protective effect of CF extract on FeSO4-induced cytotoxicity, cell viability was measured after NIH3T3 fibroblasts were pretreated with 130 or 160 μg/mL of CF extract for 2 hours, and also, DPPH-radical scavenging activity and the inhibitory activity of LDH were assessed on CF extract. In this study, FeSO4 significantly decreased cell viability in dose-dependently compared with control, and XTT50 value was calculated at 33.4 μM of FeSO4. In the protective effect of vitamin E, it significantly increased cell viability damaged by FeSO4-induced cytotoxicity. In the protective effect of CF extract on FeSO4-induced cytotoxicity, CF extract significantly increased cell viability which was decreased by FeSO4, and also it showed DPPH-radical scavenging activity and the inhibitory effect of LDH activity. From these results, it is suggested that the oxidative stress is involved in the cytotoxicity of FeSO4, and also, CF extract effectively prevented FeSO4-induced cytotoxicity by antioxidative effect. Conclusively, the natural plant extract such as CF may be a putative resources for beauty by the prevention or diminution of the cytotoxicity of hair dye component such as FeSO4 correlated with oxidative stress.