Forkhead box k1 (FOXK1) is a member of the FOX class of transcription factors and it is dysregulated in many solid tumors including hepatocellular carcinoma, gastric cancer, colorectal cancer and prostate cancer. However, the expression status of FOXK1 and its clinical significance in esophageal cancer (EC) is still uncertain. Our study aimed at investigating the significance of FOXK1 expression in human EC and its biological function in the development of EC. We found that FOXK1 was overexpressed in EC tissues compared with corresponding non-tumor tissues using immunohistochemistry. And high FOXK1 expression was related to poor differentiation of EC. The Kaplan-Meier curve indicated that high FOXK1 expression may result in poor prognosis of EC patients. Furthermore, overexpression of FOXK1 in EC9706 cell inhibited cell apoptosis and promoted cell proliferation and migration, and suppression of FOXK1 in EC109 cell obtained reverse results. Our data suggest that FOXK1 plays an oncogenic role in EC pathogenesis and can serve as a therapeutic target for patients with EC. (C) 2017 Elsevier Inc. All rights reserved.