Abstract: 【Objective】This study was carried out to probe the molecular mechanism of inactivated influenza virus vaccines immunity and find new anti-avian influenza virus genes. In addition, this study may provide candidate genes for producing anti-avian influenza virus transgenic chickens. 【Method】 40 Abar acer chickens(AA) were selected randomly in this study, 20 of which were injected H5 inactivated influenza virus vaccines ,the other 20 were controls. The 40 chickens were killed. Spleen was saved in liquid nitrogen. mRNA differential display PCR and reverse Northern dot bloting were used to find differential expressed genes between injected group and uninjected group. 【Result】13 ESTs were found via DDRT-PCR、reverse northern dot blot, 9 of which in injected group, the other 4 were in control. All 13 ESTs were compared with nucleotide sequences deposited in the nr database and the dbEST database of Genbank via BLASTn tool. DD10 and DD13 were found similar to gallus mRNA for ribosomal protein L7a. DD3, DD4, DD6, DD9, DD11 and DD12 ESTs had their highly similar nucleotide sequences in nucleotide databases but with unknown functions. The other 4 ESTs had no significant similarity with existing genes or ESTs and were regarded as new ESTs. The 4 new ESTs were submitted to GenBank(Accession number: EB714185, EB714186, EB714187, EB714188). 【Conclusion】 Gallus ribosomal protein L7a is probably connected in Avian Influenza vaccines immunologic process and anti-virus process but its exact mechanism needs further study.