Introduction: The esophagus squamous cell carcinoma (ESCC) is one of the most deadly malignances, and a current challenge is the development of effective therapeutic agents. Our present work addressed the effect of HIF-$1{alpha}$ siRNA alone or in combination with cisplatin on the growth of ESCC in nude mice. Materials and Methods: Xenografts were established by inoculating ESCC TE-1 cells in nude mice, and transplanted tumors were treated with HIF-$1{alpha}$ siRNA, cisplatin alone or together. Growth was assessed by measuring tumor volume. HIF-$1{alpha}$ mRNA and protein expression were detected using RT-PCR and immunohistochemistry, respectively. Apoptosis of ESCC TE-1 cells was analyzed by flow cytometry. Results: In our nude mice model, HIF-$1{alpha}$ siRNA effectively inhibited the growth of transplanted ESCC, downregulating HIF-$1{alpha}$ mRNA and protein expression, and inducing ESCC TE-1 cell apoptosis. Notably when combinated with cisplatin, HIF-$1{alpha}$ siRNA showed synergistic interaction in suppressing tumor growth. Furthermore, the proportion of apoptotic cells in HIF-$1{alpha}$ siRNA plus cisplatin group was significantly higher than that in cisplatin or HIF-$1{alpha}$ siRNA-treated groups (P<0.05). Conclusions: Down-regulated HIF-$1{alpha}$ expression induced by siRNA could effectively suppress the growth of transplanted ESCC $in$ $vivo$. HIF-$1{alpha}$ siRNA could enhance the cytotoxicity of cisplatin, which suggests that a combination of these two agents may have potential for therapy of advanced ESCC.