Abstract:Abstract: To look antigenic epitope of EM18. The gene fragment of EM18 was amplified from RNA of Alveolar Echinococcosis with RT-PCR,The secondary structure and surface properties of Eppin, such as physical and chemical properties, hydrophilicity, accessibility, antigencity and plasticity,were analyzed by a variety of methods. Protein 3D structure were predicted by Robetta. Many regions antigenic epitopes of EM18 were identified by computation, the possible B cell epitopes of which is in the regions of 28-43、49-55、59-64、69-79、85-91、99-111、119-129、135-144. These results indicated that there are 8 antigen epitopes in EM18 antigen determined by bioinformatics methods,which are significant in the further research of EM18 antigenic and development of dominant epitope vaccine.