OBJECTIVE To investigate the expression of zonula occluden-1(ZO-1) in hypopharyngeal squamous cell carcinoma(HSCC) and its clinical significance.METHODS Immunohistochemistry with tissue microarrays was used to detect the expression of the ZO-1 protein in 52 cases of HSCC.The correlation of prognosis and clinicopathological features was analyzed.RESULTS The expression of ZO-1 protein in HSCC was lower than that in adjacent tissues,its expression was closely related with tumor differentiation,tumor stage,tumor location and lymphatic metastasis.The Log-rank univariate analysis showed that the prognosis of HSCC was related to tumor differentiation,tumor stage,lymphatic metastasis and tumor location.The patients with lower expression of ZO-1 showed the worse prognosis than patients with higher expression of ZO-1.As shown in the Cox regression analyses,tumor differentiation,lymphatic metastasis,the ZO-1 expression and tumor stage were all independent prognostic factors.CONCLUSION The ZO-1 can serve as an independent prognostic factor of HSCC,and the low expression of ZO-1 is closely related to poor prognosis.