Brucellosis and tuberculosis are major infectious and contagious bacterial diseases in cattle. These diseases are malicious diseases that must be inspected at the slaughterhouse of cattle in accordance with the practice of quarantine in Korea. Furthermore, both diseases lead to abortion, reproductive disorder, and calf disease, causing major difficulty in the breeding of Korean Native cattle (Hanwoo), a representative industrial animal currently being raised in Korea. Co-infections of these diseases intensify clinical symptoms such as abortion and have a particularly significant effect on increasing mortality. Thus, serological tests were performed in Hanwoo, to establish the association of co-infection between brucellosis and tuberculosis in cattle. ELISA and PCR tests were conducted on blood samples collected from a total of 102 cattle in Jeonnam province, Korea, to detect brucellosis and tuberculosis infections. The PCR results revealed that 41 samples tested positive for Brucella abortus (B. abortus ) infection (40.20%), and 5 samples tested positive for Mycobacterium bovis (M. bovis ) (4.90%) infection confirmed by PCR. Notably, 9.76% (4/41) of the cattle infected with brucellosis also tested positive for tuberculosis. In conclusion, this study highlights the co-infection of...