Gastric outlet obstruction is the clinical and pathophysiological consequence of any disease process that produces a mechanical impediment to gastric emptying. It classified into benign and malignant group. Distal gastric cancer form 35% of cases with malignant gastric outlet obstruction. To study the causes of malignant gastric obstruction and how to treat them, in addition the application of gastric outlet obstruction score in our patient pre- and post-treatment. Between January-2012 to January-2014, a prospective study involves all patients with malignant gastric outlet obstruction in the surgical department in the gastrointestinal and Hepatology teaching hospital. A total of 51 cases of malignant gastric outlet obstruction were enrolled in the research, with mean age 53.21 +/- 14.6 years. There were 30 male patients [58.8%] with male to female ratio = 1.4: 1. Non-bilious vomiting was present in [100%] of cases. antropyloric region was found in [47.1%] patients. Regarding GOOS, there were improvement in all patients [p value =0.048] . Distal gastrectomy done in 19.6% of patients and gastrojujenostomy performed in 80.3% of patients. Gastric adenocarcinoma found in 15.7%, in 47.05% of patients was found to have metastatic adenocarcinoma. Gastric outlet obstruction poses diagnostic and therapeutic challenges to general surgeons. In recent years malignant cause become more. Gastric outlet obstruction score has a role in management of patients. Distal gastrectomy is the treatment of choice in resectable cases, while gastrojujenostomy can be used in advanced cases