BACKGROUND Recent studies show that peroxiredoxin 1 (Prdx1) contributes to the progression and poor prognosis of carcinoma through multiple mechanisms. However, there is little information on its expression and prognostic value in gastric cancer. This study investigated the expression of Prdx1 in gastric cancer, along with evaluating its clinical-pathological and prognostic importance. MATERIAL AND METHODS A total of 189 pairs of gastric cancer and paracarcinomatous tissues were assessed for Prdx1 expression and its association with clinical characteristics. The molecular mechanism was further investigated through in vitro experimentation. RESULTS The mRNA and protein levels of Prdx1 in the GC tissues were higher than in the peri-tumor tissues. We also found that high Prdx1 expression was positively correlated with the lymph node invasion and poor prognosis. It also served as an autonomous prognostic factor for patients with gastric cancer. Moreover, Prdx1 regulates the invasion and metastasis of GC cell lines through inhibiting E-Ca expression. CONCLUSIONS Prdx1 can promote epithelial-mesenchymal transition and gastric cancer progression. Therefore, it might be a therapeutic target and prognostic indicator for gastric cancer patients.