Objective To investigate condition of single drug or multiple drug resistance and sensitivities of different combinations of antibiotics in Helicobacter pylori (H.pylori) infected patients of different ages in Jiaxing City,Zhejiang Province.Methods From January 2007 to December 2011,a total of 6280 patients underwent gastroendoscopy examination were enrolled,the average age of them was 50.8 years old.Among them,129 cases were less than 20 years old,1802 cases were between 20 and 40,3016 cases were between 40 and 60,and 1333 cases were over 60.The mucosa of gastric antrum was collected for H.pylori culture.Drug sensitivity of isolated H.pylori strains was tested with metronidazole,amoxicillin and gentamycin,furazolidone,clarithromycin and levofloxacin.x2 test was performed for the comparison of drug resistance among different age groups.Results Among 6280 specimens,H.pylori culture of 2311 cases was positive (positive rate 36.80％).The positive rate of patients aged between 40 and 60 was the highest (38.43％,1159/3016),and that of patients over 60 was the lowest (33.76％,450/1333).The drug resistance rate of metronidazole in patients between 20 and 40 years reached 98.02％ (644/657) and was the highest.The drug resistance rate of clarithromycin in patents over 60 years old was the highest,which was 22.67％(102/450).The drug resistance rates of the levofloxacin,furazolidone,amoxicillin and gentamicin were low of all ages.Mixed resistance of two antibiotic appeared in 586 strains,mixed resistance rate of metronidazole and clarithromycin was the highest (259 strains,15.23 ％).Mixed resistance of three drugs appeared in 49 strains,mixed resistance rate of metronidazole,clarithromycin and levofloxacin was the highest (32 strains,12.88％).A total of 1691 strains were sensitive to the combination of amoxicillin and gentamycin,the sensitive was rate 99.41％.The sensitive rate of the combination of amoxicillin and furazolidone,gentamycin and furazolidone was both 94.24％.Conclusions Metronidazole presented high drug resistance of all ages,and should not be chosen.The combination use of amoxicillin and gentamicin is the ideal antibiotic combination for different ages.The combination of gentamycin and furazolidone is recommended for patients who are allergic to penicillin.