Objective To investigate the expression of New York esophageal squamous cell carcinoma 1 (NY-ESO-1) in hepatocellular carcinoma (HCC) tissues and its clinical significance, in order to provide reference for clinical treatment of this disease. Methods The clinicaldatas of 71 patients with HCC underwent surgical treatment admitted to Anqing Medical Center of Anhui Medical University from January 2013 to December 2019 were retrospectively analyzed, the paraffin-embedded liver cancer tissue and paracancer tissue samples were collected after surgery, as the HCC group and the paracancer group respectively; the clinical datas of 30 patients with hepatic hemangioma or intrahepatic bile duct calculus were retrospectively analyzed, the paraffin-embedded normal liver tissue samples were collected after surgery, as the normal group. The expression of NY-ESO-1 protein in the three groups were detected by immunohistochemical staining; the relationship between NY-ESO-1 protein expression and clinicopathologic features of HCC patients were analyzed; the risk factors of the prognosis of HCC patients were analysed by Cox proportional risk regression model. Results The positive expression rate of NY-ESO-1 protein in the HCC group was significantly higher than that in the paracancer group and the normal group; the proportion of patients with tumor diameter ≥5 cm, Ⅱ?a~?Ⅱ?b stage, Edmondson grade Ⅲ / Ⅳ grade, Ki-67 high expression, microvascular invasion (MVI) grade M1/2 grade in patients with NY-ESO-1 protein positive expression were significantly higher than that in patients with NY-ESO-1 protein negative expression; the overall survival rate of patients with NY-ESO-1 protein positive expression was significantly lower than that of patients with NY-ESO-1 protein negative expression; the results of univariate and multivariate analysis of Cox proportional risk regression model showed that, tumor diameter ≥?5 cm, Ⅱa~Ⅱb stage, Edmondson grade Ⅲ / Ⅳ grade, Ki-67 high expression, MVI grade M1/2 grade, and NY-ESO-1 positive expression were all the risk factors for the prognosis of HCC patients (HR=4.106, 2.184, 5.579, 13.967, 3.296, 2.735) (all P<0.05 ). Conclusion NY-ESO-1 is highly expressed in HCC tissues, and the tumor diameter ≥?5 cm, Ⅱa~Ⅱb stage, Edmondson grade Ⅲ/Ⅳgrade, Ki-67 high expression, MVI grade M1/2 grade, and NY-ESO-1 positive expression are all the risk factors for the prognosis of HCC patients. In clinic, the corresponding measures can be taken according to the above factors, in order to improve HCC patients’ outcomes.