The aim of this study was to assess clinical outcomes of endoscopic stenting for a gastric outlet obstruction caused by gastric cancer and the prognostic factors for stent patency by reviewing medical records. Eighty-one stents were inserted into 75 patients (48 men, average age 66 years). The technical and clinical success rates were 98 and 87%, respectively. The median stent patency was 55 days (95% CI 40-70 days). The median survival was 79 days (95% CI 58-123 days). Stent reobstruction caused by tumor ingrowth or overgrowth occurred in 25 cases (31%). Cox multivariate regression analysis showed that covered stents (odds ratio 0.29, 95% CI 0.11-0.76; P = 0.01) and chemotherapy after stent placement (odds ratio 0.34, 95% CI 0.13-0.91; P = 0.03) were significant prognostic factors for stent patency. This study found that endoscopic stenting is a safe and effective palliation treatment for malignant gastric outlet obstruction and a covered stent and chemotherapy are significant prognostic factors for stent patency.