The resistance of Helicobacter pylori to antimicrobials, known to be increasing in many countries, is an important factor compromising the efficacy of eradication therapy. Therefore, our study aimed at analysing the current susceptibility status of H. pylori in Poland. A total of 337 H. pylori isolates were cultured from children (N=179) and adults (N=158) from various regions of the country from January 2001 to December 2004. All strains were susceptible to amoxicillin and tetracycline. The overall resistance to clarithromycin (CL) was 28%, but there were significant differences between the centres (ranging from 0% to 33%) and between child and adult isolates (28% versus 15%, respectively; P=0.01) for primary a resistance. Altogether, 46% of H. pylori isolates were resistant to metronidazole (MTZ) and 20% of isolates were simultaneously resistant to CL and MTZ.