Objective: To investigate the expressionof proline-rich protein 11 (PRR11) in esophageal carcinoma (EC) tissues and to study it’s effect on the proliferation and metastasis of human EC TE-2 cells in vitro. Methods: Eighty patients were pathologically diagnosed with EC the Department of Thoracic Surgery of the Second Affiliated Hospital of Zhengzhou University from October 2016 to October 2018, and their surgically resected cancer tissues and corresponding para-cancerous tissues were collected for this study. qPCR was used to detect the expression of PRR11 mRNAin tissues or cells. Log-rank Test was used to analyzethe relationship between the expression of PRR11 in EC tissues and general data, histological type, lymphatic metastasis, depth of invasion and TNM stageof the EC patients. Kaplan-Meierplot was used to analyze the association between PRR11 mRNA and patients’prognosis. TE-2 cells were transfected with lentivirus shRNA to construct cell line with PRR11 knockout and corresponding control cell lines, as shPRR11#1, shPRR11#2 and control group. qPCR and WB assays were used to verify the mRNA and protein expressions of PRR11 in cell lines respectively. MTT was used to examine the proliferation of transfected cells, and Transwell experiments were used to detect cell invasion and migration. Results: The expression of PRR11 mRNA in EC was higher than that in para-cancer tissues (P<0.05). There was significant correlation between PRR11 over-expression and histological type, lymphatic metastasis, depth of invasion and TNM stage(all P <0.05), and high PRR11 expression was significantly related with the poor prognosis of EC patients (P<0.05). The mRNA and protein expressions of PRR11 in cells of shPRR11#1 and shPRR11#2 groups were significantly lower than those in control group (all P <0.05). MTT assay showed that the proliferation of cells in shPRR11#1 and shPRR11#2 groups was significantly lower than that in the control group (P<0.05 or P<0.01). The results of Transwell invasion and migration assays showed that the average number of cells with in each field of viewin shPRR11#1 and shPRR11#2 groups was significantly lower than that in the control group (P<0.01). Conclusion: PRR11 is over-expressed in EC tissues and PRR11 over-expression is closely related to the occurrence, progression and prognosis of esophageal cancer. In vitro experiments have also demonstrated that knockdown of PRR11 can inhibit the proliferation, invasion and migration of EC. PRR11 can be used as a potential molecule marker and drug targets for EC. ··