A preliminary epidemiological investigation of Helicobacter pylori (HP) infection was performed with 13C-urea breathing test for 218 residents at the age from 40 to 69 years in a high risk area of gatric cancer, Linqu County of Shandong province. Our results show an overall HP infection rate of 71.10%, or 69.49% for men and 73.00% for women. The HP infection rate in the group of serious chronic atrophic gastritis was significantly higher than that of mild chronic atrophic gatritis (P < 0.05). The HP positive group also has a higher rate of complaining about gastric discomfort than the HP negative group (P < 0.02).