PURPOSE: The prognosis for gastric cancer patients with distant metastasis is very poor. The purpose of this study was to evaluate the prognosis and survival for gastric cancer patients with synchronous metastasis. METHODS: Among 2,083 gastric cancer patients who received surgery at the Department of Surgery, Hanyang University Hospital from 1992 to 2009, 164 patients revealed distant metastasis. However, 3 patients who died of postoperative complications were excluded. For the remaining patients, various clinicopathological factors were analyzed using univariate and multivariate survival analyses. RESULTS: Systemic chemotherapy (SC), type of surgery, lymph node dissection, degree of peritoneal carcinomatosis (PC), presence of ascites and tumor location were significant prognostic factors. However, sex, age, number of metastatic sites and histologic classification were not significant prognostic factors. In multivariate analysis, the type of surgery, the SC and the degree of PC were independent prognostic factors. Survival benefit by SC was significant in single site metastasis. The significant survival difference between resection and non-resection groups was observed regardless of number of metastatic sites. CONCLUSION: In gastric cancer patients with metastasis, the favorable prognostic factors were type of surgery and SC in single metastasis. The gastrectomy improves the prognosis regardless of number of metastatic sites. However, a prospective randomized clinical trial is mandatory to attain more accurate information.