Extensive granuloma formation typical of tuberculosis was observed in a mature female emu. The diagnosis was confirmed by demonstration of acid-fast bacilli in lesions and culture of a Mycobacterium with growth characteristics resembling M. avium from liver tissue. Individual emus on the affected farm and an epidemiologically related unit gave a positive skin reaction to intradermal M. avium tuberculin. The implication of tuberculosis in commercial emus is noted in relation to the growth of the industry in North America and to management and commercial practices that encourage dissemination of infection within the species and to other exotic and domestic animals.