The main aim of this study was to investigate the roles of GST-${pi}$ and $pol{eta}$ genes in the chemoresistance of esophageal carcinoma cells. Eukaryotic expression vectors containing each gene were constructed and transfected into EC9706 cells, and the biological effects of the two genes assessed based on a resistance index. We additionally investigated the in vitro and in vivo anti-resistance effects of GST-${pi}$ and $pol{eta}$ genes using recombinant lentiviruses carrying siRNAs against the two genes. Our results showed that upregulation of GST-${pi}$ and $pol{eta}$ genes suppresses chemosensitivity of esophageal carcinoma cells to cisplatin, while downregulation of these two genes with RNAi technology reverses this chemoresistance. Multi-site injection of recombinant lentivirus targeting the GST-${pi}$ gene into transplanted cDDP tumors effectively reversed their chemoresistant phenotype. However, the same treatment against the $pol{eta}$ gene did not lead to significant efficacy against chemoresistance.