Objective: To investigate the relationship of the expression of peccadillo ibosomal biogenesis factor 1 (PES1) in tumor tissues of patients with gastric cancer between the development and prognosis of gastric cancer. Methods: A total of 89 gastric cancer patients who received radical gastrectomy in Minhang Hospital Affiliated to Fudan University from January 2012 to January 2013 were collected. The expression of PES1 in gastric cancer tissues was detected by immunohistochemical staining and Western blot, and the expression level of PES1 was compared with that of matched adjacent non-tumor gastric tissues. The correlation between PES1 expression in tumor specimens and clinicopathological characteristics was analyzed to study the relationship between PES1 expression and gastric cancer progression. The relationship between PES1 expression and patients outcomes was analyzed by univariate analysis. Results: PES1 is highly expressed in gastric cancer tissues, and its high expression is positively correlated with the depth of invasion, lymph node metastasis and T stage of gastric cancer (all P<0.05). PES1 expression may be an independent prognostic marker of overall survival (OS) and progression-free survival (RFS) in patients with TNM stage I. Conclusion: The high expression of PES1 is positively correlated with the progress of gastric cancer and can be used as a target molecule for prognosis monitoring.