Resveratrol (Res) has been reported to elicit many cellular responses including cell cycle arrest, differentiation, and apoptosis. This makes it a novel and potential anticancer agent. Moreover, the lipophilicity of Res raises the possibility of its application as a potential model drug in nanoparticle based delivery systems. Resveratrol is incorporated into mPEG-PCL based nanoparticles with high encapsulation efficiency due to its lipophilicity. The significant finding of the current study is that Res-loaded nanoparticles at lower concentration could lead to significantly higher cell death compared to equivalent dose of free Res and this difference of cytotoxicity could not be abrogated by the antioxidant Vitamin E. Furthermore, free Res shows significant less cytotoxicity than the equivalent dose of Res-loaded nanoparticles with the preconditioning of Vitamin E. Meanwhile, reactive oxygen species (ROS) determination revealed the significantly lower intracellular ROS levels in Res-treated cells compared to nanoparticle-treated cells. Therefore, the differential cytotoxicity between Res and Res-loaded nanoparticles may be mediated by the discrepancy of intracellular ROS levels. The present results suggest that Res-loaded nanoparticles could be a potential useful chemotherapeutic formulation for malignant glioma therapy and the development of traditional Chinese medicine with nanoscale drug formation warrants more intensive research in order to evaluate its clinical feasibility.