The invention discloses a 
recombinant baculovirus for expressing heat-resistant 
HN protein of the 
Newcastle disease virus as well as a preparation method and application of the 
recombinant baculovirus. The 
virus strain is preserved in China Center for Type Culture Collection, the preservation address is Wuhan University, Wuhan, China, and the preservation number is CCTCC NO: V202044. The preparation method of the ecombinant baculovirus comprises the following steps of carrying out 
point mutation on an HN 
gene of a 
Newcastle disease virus non-heat-resistant LaSota strain, including G49E, R269S,G293E, R353Q and G494D, inserting the mutated HN 
gene into a baculovirus 
genome, and carrying out virus rescue to obtain the 
recombinant baculovirus rAC-HN-N5 strain. The 
virus strain can efficientlyexpress 
mutant HN protein. Compared with wild-type 
HN protein of the LaSota strain, the 
mutant HN 
protein has the 
advantage that the 
thermal stability is obviously enhanced. The 
mutant HN 
protein expressed and purified by utilizing the recombinant baculovirus rAC-HN-N5 strain can be used for preparing a heat-resistant 
subunit vaccine for the 
Newcastle disease, so that the dependence of the vaccine on a 
cold chain is reduced, and a new thought is provided for the development of the 
subunit vaccine with 
high heat stability.