Poland is officially free of animal tuberculosis (TB), caused by Mycobacterium bovis and closely related members of the Mycobacterium tuberculosis complex, including Mycobacterium caprae. Sporadic cases of infection have been reported in cattle, but also in free-ranging species such as European bison (Bison bonasus), red deer (Cervus elaphus), Eurasian wild boar (Sus scrofa), Eurasian lynx (Lynx lynx), and Eurasian badger (Meles meles). This paper presents the history and recent findings regarding the incidence of tuberculosis in a free-living European bison herd and the possibility of interspecific transmission of the agent to other wildlife. The spoligotyping method indicated that the isolated strains belong to M. caprae showing spoligo pattern 2000037777377400. The results of these and earlier studies suggest that this M. caprae strain could be transferred from bison to wild boar.