The use of the COBAS AMPLICOR System (Roche Molecular Diagnostics, Basel, Switzerland), the only automated system for PCR testing, was evaluated for a rapid identification of mycobacteria with positive BACTEC 12B cultures, Two hundred ninety-six specimens with a growth index of greater than or equal to 30 Here analyzed for the presence of Mycobacterium tuberculosis complex, Mycobacterium avium, and Mycobacterium intracellulare, Compared to traditional methods and provided that samples with PCR inhibition are retested at a 1:10 dilution, the sensitivity and specificity of the COBAS AMPLICOR System with BACTEC 12B cultures were 100 and 98%, respectively. The COBAS;AMPLICOR method is rapid and reliable for identifying the most common mycobacteria in cultures.