<p><b>OBJECTIVE</b>To study the risk factor of perioperative complication in gastric cancer patients with radical therapy and its influence on prognosis.</p><p><b>METHODS</b>Clinical, pathological and follow-up data of 1 148 gastric cancer patients undergoing radical gastrectomy at Tianjin Medical University Affiliated Tumor Hospital between January 2009 and August 2011 were retrospectively collected. Pearson 2 test and Logistic regression analysis were used to analyze the risk factor of perioperative complication. Cox regression analysis was used to evaluate the influence of perioperative complications on the prognosis in patients after radical gastrectomy. Kaplan-Meier survival curve was applied to calculate the survival.</p><p><b>RESULTS</b>Of 1 148 patients, 851 were male, 297 were female, age ranged from 19 to 89 (average 59.9) years. Perioperative complication occurred in 312 cases (27.2%), including 140 cases of pulmonary infection and 53 cases of abdominal infection. Multivariate Logistic regression analysis showed that ≥65 years old (OR:0.736, 95%CI: 0.558 to 0.971, P=0.030), serum albumin less than 35 g/L(OR:2.626, 95%CI: 1.479 to 4.665, P=0.001), Borrmann type IIII((OR: 0.748, 95%CI: 0.610 to 0.917, P=0.005), tumor site at upper 1/3 of stomach (OR:1.326, 95%CI:1.167 to 1.506, P=0.000), combined organ resection(OR:0.624, 95%CI:0.428 to 0.909, P=0.014) were independent risk factors of perioperative complication. Tumor site at upper 1/3 of stomach (OR:1.649, 95%CI: 1.368 to 1.988, P=0.000), ≥65 years old (OR:0.548, 95%CI:0.379 to 0.792, P=0.001), without intraoperative chemotherapy (OR:1.671, 95%CI:1.146 to 2.437, P=0.008) were independent risk factors of perioperative pulmonary infection; Borrmann type IIII((OR:0.576, 95%CI:0.369 to 0.900, P=0.015), with intraoperative chemotherapy (OR:0.431, 95%CI:0.230 to 0.810, P=0.009), intraoperative blood loss ≥400 ml(OR:0.411, 95%CI:0.176 to 0.959, P=0.040) and combined organ resection (OR:0.412, 95%CI:0.215 to 0.789, P=0.008) were independent risk factors of perioperative intraperitoneal infection. Cox regression analysis revealed that without intraoperative chemotherapy, proximal subtotal or total gastrectomy, TNM stage III(, N3 stage lymph node metastasis, positive soft tissue outside lymph node, combined organ resection and organ failure were independent risk factors affecting the prognosis of gastric cancer patients after radical resection (all P<0.05), however the perioperative complication was not independent risk factor affecting the prognosis (P=0.259). The median survival time was 35 months, and 5-year survival rate was around 38.7%. The median survival time of gastric cancer patients with operative complications and without complications were 28.0 and 36.5 months, and the 5-year survival rates were 37.2% and 39.3%, whose difference was not statistically significant (P=0.259).</p><p><b>CONCLUSION</b>There is a higher risk of perioperative complication in those gastric cancer patients with old age, preoperative low serum albumin level, tumor site at upper 1/3 of stomach, Borrmann type IIII(, intraoperative combined organ resection, while the perioperative complication has no significant effects on the long-term survival.</p>