Objective：To investigate the expression of Cutaneous T cell lymphoma associated antigen 15(CTAGE15) in esophageal squamous cell carcinoma (ESCC) and its association with clinical prognosis in patients, as well as its impact on the proliferation, invasion, and migration abilities of ESCC cells.Methods:Kaplan-Meier analysis was used to analyze the impact of CTAGE15 on the prognosis of ESCC patients in public database.?The mRNA expression levels of CTAGE15 in esophageal epithelial cells and ESCC cells were measured by qRT-PCR. Furthermore, the expression of CTAGE15 was detected in cancer and adjacent tissues from 120 ESCC patients with complete follow-up information.COX proportional survival risk model was enrolled to analyze the survival risk factors of ESCC patients, and multivariate correlation analysis was used for the analysis of the association of CTAGE15 with the clinicopathology of ESCC patients. Kaplan-Meier analysis was employed to analyze the effect of CTAGE15 on the prognosis of ESCC patients.The knockdown of CTAGE15 in ESCC cells was achieved using small interfering RNA (siRNA), and changes in cell proliferation, invasion, and migration abilities were assessed.Results:The public database showed CTAGE15 expression was significantly associated with overall survival (P<0.05) and disease-specific survival (P<0.05) in ESCC patients,and higher expression being correlated with better survival.qRT-PCR results revealed significantly higher expression of CTAGE15 in ESCC tissues and cells compared to normal esophageal epithelial tissues and cells.In addition, the expression of CTAGE15 was significantly correlated with T stage and N stage of ESCC patients,and higher expression being associated with earlier TN stage.Knockdown of CTAGE15 enhanced the proliferation, migration, and invasion abilities of ESCC cells(P<0.05).Conclusion: CTAGE15 was positively correlated with the prognosis of ESCC patients and it can inhibit the proliferation, invasion, and migration abilities of ESCC cells.