Objective To analyze the relationship between helicobacter pylori (HP) and gastric cancer. Methods We searched CNKI (Jan.1995-Dec.2005) and Wangfandatabase (Jan.1995-Dec.2005). Case-control studies on relationship of helicobacter pylori infection and gastric cancer were collected. Meta-analysis method was used to sum up the odds ratio (OR) and 95%CI of these studies.Results We identified 14 case-control studies with 11 studies of healthy adults versus gastric cancer patients and 4 studies of gastritis versus gastric cancer patients. The results of subgroup analyses based on patients resource showed: statistical difference was founded between healthy adults and gastric cancer patients with pooled OR 2.00 and 95%CI 1.25 to 3.20; no statistical difference was founded between gastritis patients and gastric cancer patients with pooled OR 1.54 and 95%CI 0.68 to 3.50. The results of subgroup analyses based on locations of gastric cancer showed: statistical difference was founded between the non-cardiac gastric cancer patients and the control with pooled OR 3.60 and 95%CI 1.25 to 10.36; no statistical difference was found between cardiac gastric cancer patients and control with pooled OR 0.88 and 95%CI 0.56 to 1.39.Conclusion HP infection can be associated with gastric cancer, and the different conclusions of the 14 reports may be attributed to the locations of gastric cancer and the selection of controls.