Objective: Octreotide and aspirin have shown the growth inhibition for some tumors. However, the effects of these non-cytotoxitic agents on gastric adenocarcinoma are still largely unknown. The effects of combination of octreotide and aspirin on the growth of gastric cancer were investigated. Methods: Proliferation of gastric cancer cell line affected with octreotide or aspirin was determined by 3H-thymidine incorporation. After xenografts of human gastric cancer were implanted orthotopically in stomach, nude mice were administrated octreotide plus aspirin for 8 weeks. The mRNA of somatostatin receptor in the tissues of gastric carcinoma was detected by reverse transcription polymerase chain reaction technique. Cyclooxygenase-2 in gastric cancer tissues was measured by immunohistochemistry. Results: Both octreotide and aspirin significantly reduced the 3H-thymidine incorporation of gastric cancer cells. Xenografts in situ were found in all stomachs of nude mice except two nude mice in combination group. Either size or weight of tumors treated by octreotide or aspirin was significantly reduced when compared to that of control. The combination group showed the best inhibition in tumor growth. The inhibition rate for tumor was 60.6% in octreotide group, 39.3% in aspirin group and 85.6% in the combination group respectively. No severe side effect was observed in all of treatment groups. Somatostatin receptor-2 and 3 were expressed in the transplanted gastric adenocarcinomas. Aspirin could down regulate the strong expression of cyclooxygenase-2 in the tissue of gastric adenocarcinomas of nude mice. Conclusions： Combination of octreotide and aspirin significantly enhanced the anti-proliferative effect in gastric cancer through mediation of somatosatin receptors and suppression of cyclooxygenase-2.