Summary As a member of the catenin family, expression of δ -catenin and its clinical implication in numerous tumors remain unclear. In the present study, expression of δ -catenin in esophageal squamous cell carcinoma (ESCC) and its correlations with patient prognosis were explored. We detected the expression of δ -catenin, by immunohistochemistry, in ESCC tissues from 299 cases and analyzed the correlation between δ -catenin expression and patient clinicopathological features. Compared with a lack of expression in adjacent normal esophageal epithelium (0%, 0/47), the frequency of δ -catenin protein was increased in ESCC tissues to 41.5% (124/299, P < .001) and expression correlated with TNM stage and lymph node metastasis ( P = .025 and .019, respectively). Furthermore, Kaplan-Meier survival analysis revealed that patients with high δ -catenin expression had shorter survival than patients with low expression ( P = .010), and multivariate Cox analysis revealed that high δ -catenin expression was also an independent prognostic factor ( P = .001). In transwell assays, migration of ESCC cells was enhanced by δ -catenin overexpression, whereas proliferation of ESCC cells was unchanged. Together, our results suggest that δ -catenin acts as an oncoprotein when overexpressed in ESCC, and its expression is associated with poor prognosis and malignant cell behavior.