Background:– Mycobacterium tuberculosis remains leading cause of death from an infectious agent. Rapid diagnosis of tuberculosis and detection of Rifampicin (RIF) resistance are essential for effective disease control and management. CBNAAT (Cartridge Based Nucleic Acid Amplification Test) also known as Gene Xpert MTB/RIF assay is the new cutting edge integrated diagnostic modality for diagnosis of tuberculosis and rapid detection of RIF resistance if any in clinical specimens. Also has role in patients who are sputum smear negetive or have non–productive sputum but are clinico–radiologically suspicious of pulmonary tuberculosis. Materials and Methods:– A total of 100 patients were retrospectively assessed who had sputum for AFB negetive and or were non–productive of sputum and were clinico–radiologically suspected of pulmonary tuberculosis. All patients who do not have contraindications to bronchoscopy were subjected to procedure and bronchial aspirate was obtained. Smear and CBNAAT examination of aspirate was done. Results:–Out of total 100 patients 57% were males and 43 were females,70% patients came from rural areas ,Cough 82% was most common presenting symptom, Most common radiological abnormality was consolidation 35%, 52% patients were labelled as microbiologically confirmed cases of pulmonary tuberculosis of which BAL smear positives were 7% and BAL smear negetive but CBNAAT positive cases were 45%. Conclusion:– CBNAAT done on broncho–alveolar lavage fluid obtained via bronchoscopy can be an important adjunct to bacteriological confirmation of suspected cases who were otherwise sputum negative or not productive of adequate sputum sample. Also resistance to rifampicin can be detected prior to the treatment.