Nuclear factor E2-related factor 2 (Nrf2) plays a part in antioxidant and phase II detoxification enzymes in cells by the up regulation of many antioxidant response elements (ARE) related gene transcription. Nrf2 not only protect the normal cells, but also can protect cancer cells from the effect of cell stress, which is helpful to the survival of cancer cell. Some studies show that the expression of Nrf2 has important clinical significance in cancer patients, but the analysis of gastrointestinal tumor Nrf2 comprehensive expression has not been reported. The aim of this study is to evaluate the expression of Nrf2 in gastric cancer by immunohistochemistry and analyze its related clinical significance.180 cases of gastric cancer patients receive the gastrectomy and lymphadenectomy, and the resection of tissue is expressesd in paraffin embedded sections by immunohistochemical analysis of Nrf2. And the difference between groups use χ(2) (chi-square criterion) test, and will be analyzed by Fisher's exact test and Mann-Whitney U test. Use univariate and multivariate analysis, Kaplan-Meier curve and log-rank to test and evaluate the correlation between the expression of Nrf2 and the clinical pathological features.The immune reaction of Nrf2 is mainly found in gastric cancer cell nucleus, which positive expression is closely related to the tumor size, depth of invasion, lymph node metastasis, lymphatic invasion and histological analysis (all P<0.05). The log-rank test shows that the survival rate of Nrf2 positive expression group is significantly lower than that of the negative expression group (P<0.01). The Nrf2 positive expression is closely related to the drug resistance of adjuvant chemotherapy on the basis of 5FU (P=0.022).There is a positive correlation between the expression of Nrf2 and the invasion of gastric cancer, which can be used as a potential indicator of patients' poor prognosis.