Abstract: ObjectiveTo study the growth characteristic of mycobacteria cultured by BACTEC 960 and the patterns of smear and acid-fast staining, to provide initial comments on the identification of mycobacterium. MethodsThe clinical samples were collected from the hospital, and cultured by BACTEC 960. Five handred and thirty culture-positive isolates were performed direct smear and acid-fast staining，species identification and drug susceptibility testing. ResultsMycobacterium tuberculosis growing in the MGIT culture tube presented as the floc precipitation， showed the rope-like arrangement by smear and microscopic examination. Whereas, non-tuberculosis mycobacterium (NTM) presented as the turbid growth， showed dispersive，the regiment granular， massive， debris and loose fascicular，and other irregular arrangement under the microscope. ConclusionMycobacterium tuberculosis cultured in BACTEC 960 has the characteristic of the winding，which is very easy to be identified under the microscope, provide a primary screening role on the identification of mycobacteria.

Key words: Mycobacterium tuberculosis, mycobacteria,atypical, culture media, microscopy