AIM: To clone and characterize the oipA gene of Helicobacter pylori (H pylori). METHODS: The primers were designed based on the sequence in GenBank. PCR was used to amplify the oipA gene. The amplified fragment was inserted into plasmid pGEX-5X-1 for nucleotide sequencing. The bioinformatics analysis was carried out by using databases of Blast,NCBI CDD,Swiss-model, Propred and software of Omiga v2.0 and Antheprot v5.0. RESULTS: The oipA gene was successfully cloned with the same sequence as that published in GenBank. No homeotic gene was found in other species through the Blast, and no conserved domain was found through NCBI CDD. Potential hydrophobicity and antigenicity were predicted by software Omiga v2.0 and Antheprot v5.0. The epitopes were predicted by comparing the results from Omiga v2.0, Antheprot v5.0 and Propred. CONCLUSION: Bioinformatics analysis of gene oipA may help to elucidate the pathogenesis of H pylori related diseases and to develop H pylori vaccines.