H5N1 highly pathogenic avian influenza virus was highly pathogenic and sometimes even fatal for tigers and cats. To develop a new type of vaccine for Felidae influenza prevention, recombinant replication-competent canine adenovirus Type 2 expressing hemagglutinin gene of H5N1 subtype tiger influenza virus was constructed. A/tiger/Harbin/01/2003 (HSN1) HA gene was cloned into PVAX1. The HA expression cassette which included CMV and HA and PolyA was ligated into the E3 deletion region of pVAXdeltaE. The recombinant plasmid was named pdeltaEHA. The pdelta EHA and the pPoly2-CAV2 were digested with Nru I /Sal I, respectively. The purified Nru I/Sal I DNA fragment containing the HA expression cassette was cloned into pPoly2-CAV2 to generate the recombinant plasmid pCAV-2/HA. The recombinant genome was released from pCAV-2/HA, and was transfected into MDCK cells by Lipofectamine. The recombinant virus named CAV2/HA was gained. Anti-H5N1 influenza virus HI antibody (1:8 - 1:16) was detected in the cat immunized with CAV-2/HA.