Objective: To investigate association between PG level and HP infection in patients with chronic gastropathy and clinical significance by case control study.  Methods: To determine the serum PG level in patients with chronic gastropathy, we detect the serum PG level in 108 patients with that desease. To confirm the HP infection and the different strains of HP , we made both the serum anti-Hp antibody test and the Rapid Urease test to all the patients. With the regard to the eradication therapeutic regimen, we can make a judgement of successful treatment about 1 week by Classic trigeminy treament, when the 14C-urea Breath test(14C-UBT)was negative 4 weeks after eradication. Besides, to observe the correlation between the serum PG level and the eradication therapeutic regimen, we detected its level in these patients.  Results: Compared to the healthy control group, We found that the serum PGⅠand PGⅡlevel increased in gastric ulcer and duodenal ulcer patients(P0.05)(.3)We found that the serum PGⅠand PGⅡlevels were much higher in the peptic ulcer patients with cagA  and vacA  strains of HP infection than in the patients with cagA﹣、vacA﹣strains of HP infection(P0.05).  Conclusion : The serum PGⅠlevel and PGⅠ/ PGⅡratio increased obviously in the patients of peptic ulcer, and the serum PGⅠlevel degraded in the patients of atrophic gastritis and stomach cancer, the PGⅠ/ PGⅡratio degraded obviously in the patients of stomach cancer.The results indicated that serum PG level contributs to the evaluation of state of peptic ulcer, atrophic gastritis and stomach cancer. Compared to the patients uninfected with helicobacter pylori, the serum PG level increases obviously in the peptic ulcer patients infected with helicobacter pylori, and the serum PG level increases more obviously in the patients infected wth typeⅠhelicobacter pylori.The results indicated that gastric mucosa pathological damage accompanies with abnormality of PG secretary.Eradication of helicobacter pylori successfully may make the serum PGⅠand PGⅡlevel decrease and PGⅠ/ PGⅡratio increase in the peptic ulcer patients,and the serum PGⅡlevel decrease and the PGⅠ/ PGⅡratio increase in the atrophic gastritis patients. The results indicated that the serum PG level can be as the one of index of curative effect of eradication of helicobacter pylori.