目的鞭毛是幽门螺杆菌（Ｈｐ）的重要侵袭因子，本研究拟检测Ｈｐ鞭毛素Ａ基因的变异性，进而研究其与Ｈｐ致病性的关系．方法我们对５２例胃粘膜活检标本和１８株Ｈｐ临床分离株进行Ｈｐ特异的１６ＳｒＲＮＡ基因和鞭毛素Ａ基因ＰＣＲ扩增和ＰＣＲＲＦＬＰ及ＰＣＲＲＦＬＰＳＳＣＰ分析．结果对４３例Ｈｐ（＋）的ｆｌａＡ基因ＰＣＲＲＦＬＰ（ＨｉｎｄⅢ）大约可分７个型（变异检出率为１６３％），而ＰＣＲＲＦＬＰＳＳＣＰ可分３７个型（变异检出率为８６０％），两者有非常显著性差异．结论ｆｌａＡ基因变异性极大，ＰＣＲＲＦＬＰＳＳＣＰ优于ＰＣＲＲＦＬＰ，是检测其变异的有效方法． Objective Flagella is an important invasion factor of Helicobacter pylori (Hp). In this study, we intend to detect the variation of Hp flagellin A gene and further study its relationship with Hp pathogenicity. Methods 52 cases of gastric mucosal biopsy specimens and 18 strains of Hp clinical isolates were Hp-specific 16SrRNA gene and flagellin A gene PCR amplification and PCR  PCR and PCR  RFP  SSCP analysis. Results The PCR-RFLP (HindⅢ) of flaA gene of Hp (+) in 43 cases was divided into seven types (mutation detection rate was 163%), and PCRRFLPSSCP could be divided into 37 types The rate was 86  0%), the two have very significant differences. Conclusion The flaA gene has great variability, PCRRFLPSSCP is superior to PCRRFLP, which is an effective method to detect the variation.