Despite low sensitivity in detection of Mycrobacterium tuberculosis, acid-fast sputum smear remains the main diagnostic method in most country. Mycobacterial culture is the gold standard and the most sensitive method for TB diagnosis. Recently, in 2011, WHO endorsed the wide use of Xpert MTBIRIF (MTB: Mycobacterium tuberculosis
RIF: rifampicin) assay, a fully automated diagnosis molecular test using real-time polymerase chain reaction technology to simultaneously detect TB and rifampicin resistance in the rpoB gene. To initially assess the effectiveness of the new technique GeneXpert in the Department of Microbiology- Viet Tiep Hospital Haiphong, the Xpert MTB/RIF carried out with the acid - fast sputum smear method for 436 sputum specimens of 436 patients. The result: The patient was found to have TB bacteria in men is 5 times higher than women and patients with high risk of tuberculosis at the age of 40. The sensitivity of GeneXpert MTB/RIF detected MTB (+) was 95.7 percent in the acid - fast sputum smear AFB (+). 49 smears AFB(-), GeneXpert MTB test (+), demonstrate the sensitivity GeneXpert is higher than the Ziehl Neelsen stain. In 94 sputum specimens MTB (+),GeneXpert detected 10 specimens RIF resistance(equivalent10.64 percent). Conclusion: The GeneXpert in detecting TB and rifampicin resistance from sputum specimens may help in early diagnose TB with good sensitivity, simple process, safe for staffs, and help in treatment patients who had multi-drug resistane tuberculosis.