Aims: Previous studies revealed that drug-loaded poly(ethylene-glycol)-poly(γ-benzyl-L-glutamate) (PEG-PBLG) nanoparticles exhibit favorable pharmacokinetic characteristics in the treatment of oral squamous cell carcinoma (OSCC). In this study, the characteristics and anticancer effect of herpes simplex virus thymidine kinase (HSV-TK)-loaded PEG-PBLG nanoparticles for OSCC were investigated. Materials & methods:HSV-TK-loaded PEG-PBLG nanoparticles were prepared and their morphology, DNA protection and gene-transfer efficiency were evaluated. Their anticancer effect in vitro and in vivo was determined. Results & discussion:HSV-TK-loaded PEG-PBLG nanoparticles have a core-shell structure and DNA protection and higher gene-transfer efficiency. PEG-PBLG nanoparticle-mediated HSV-TK/ganciclovir (GCV) had a strong anticancer effect on Tca8113 cells in vitro and buccal carcinoma induced in golden hamsters. Conclusion: PEG-PBLG nanoparticles may be a superior gene carrier in future clinical applications because of their DNA protection and higher gene-transfer efficiency. The HSV-TK/GCV suicide-gene system had significant antitumor effects on OSCC.