Objective To investigate the molecular mechanism of interleukin-17 in the development of gastric cancer through NF-κB signaling pathway. Methods Thirty patients with gastric cancer in Wuwei Cancer Hospital of Gansu province and 30 control individuals who had physical examination in the hospital at the same time were selected. The expression of IL-17,IL-6 and IL-8 in serum of patients with gastric cancer and control was detected by ELISA.The pathological changes of gastric cancer were observed by microscopy with HE staining; Immunohisto-chemistry method was used to detect the expression of IL-17, NF-κB p65, IKK-β and IL-6 in gastric cancer tissues, adjacent tissues and gastric tissues far from cancer tissues.The expressions of IL-17, NF-κB p65, pNF-κB p65, IKK-β and IL-6 in gastric cancer tissues, adjacent tissues and gastric tissues far from cancer tissues were detected by Western blot. Results IL-17, IL-6 and IL-8 were up-regulated in serum of gastric cancer patients compared with healthy controls group(P＜0.