Abstract: Objective: To observe the ultrastructure of gastric cancer with electron microscopy and to discuss its relationship with postoperative survival. Methods: Tissues were collected from 160 cases of gastric cancer that had been followed up for over 5 years. Immunohistochemical staining of the tissues for NSE, Syn, and CgA showed positive staining in 80 cases. Tissues of these 80 cases were observed with electron microscopy and the corresponding data was analyzed by Stata 7.0 software. Results: Neuroendocrine granules were found in 39 cases, and the electron microscopic detection rate was 23%(39/168). The postoperative survival time of patients with gastric cancer with neuroendocrine differentiation was shorter than that of those with gastric cancer without neuroendocrine differentiation, with a significant difference between the two types (P=0.0032). Conclusion: It is critical to identify gastric cancer with neuroendocrine differentiation. Patients who have gastric cancer with neuroendocrine differentiation have shorter postoperative survival time and poorer prognosis. Observation with electron microscopy is a reliable method of diagnosis.