The aim is to investigate the effect of Magnolol preserved H460 cells from an oxidative agent tert-butylhydroperoxide (TBHP)-induced cell death. Magnolol augmented cell survival ratio after TBHP challenged. The protective action of this drug was more efficacious than that of N-acetylcysteine (NAC) which is a putative antioxidant. DNA damage, detected by the comet assay, was diminished after treatment of Magnolol. The cells viability decreased after treatment with 0.15 mM TBHP for 24 h, accompanied by inducing apoptotic death of the cells. Cytotoxicity and apoptosis induced by TBHP were significantly inhibited or attenuated after pretreatment with 20 microM Magnolol. Magnolol contributes to the cells survival through downregulated the p53 phosphorylation and PTEN expression, and upregulated Akt phosphorylation. Taken together, Magnolol was effective against DNA single strand breaks (SSB) formation, cytotoxicity and lipid peroxidation induced by TBHP, and its effects on p53 phosphorylation, PTEN and Akt phosphorylation were due to its antioxidative function, and partially via a p53 dependent mechanism in this protective effects.