The invention provides antituberculous recombinant bacillus calmette-guerin (BCG 
delta mazG) with a mazG 
gene deleted. The mazG 
gene in a 
genome of the antituberculous recombinant bacillus calmette-guerin with the mazG 
gene deleted is replaced with a hygromycin resistant gene. The invention further provides a preparation method of the BCG 
delta mazG and application thereof in preparing a recombinant vaccine for preventing 
tuberculosis. After the BCG 
delta mazG is inoculated subcutaneously into a mouse, a 
T cell immune response is obviously improved, after the immunized mouse is infected with a 
mycobacterium tuberculosis standard strain H37Rv, the bacterial load of the infected animal 
lung and 
spleen is significantly decreased, the 
pathological degree is relieved, and after the immunized mouse is infected for five weeks, a 
T cell secondary immune response is significantly improved. It is found through bacterial in-vivo survival tests that after high-
dose intravenous 
inoculation is conducted, the BCG delta mazG can survive on viscera of the 
spleen, the 
lung, the liver and the 
kidney of the mouse continuously for 20 w or above, and the amount of 
bacteria of a BCG delta mazG recombinant strain is obviously increased compared with a 
wild strain. It is proved through experiments that the BCG delta mazG recombinant strain has antituberculous 
immunogenicity, protective 
efficacy and in-vivo persistence activity which are significantly improved, and the antituberculous recombinant bacillus calmette-guerin (BCG delta mazG) with the mazG gene deleted is expected to become one of the novel candidate vaccines for preventing 
tuberculosis infection.