Objective To compare the diagnostic value and healtheconomic value of rapid detection of mycobacterium tuberculosis andrifampicin resistance (XpertMTB/RIF), mycobacterium nucleic acidPCR-fluorescent probe detection (MTB-NTM-PCR) and RNA isothermalamplification real-time fluorescence detection (SAT-TB) in detectingbronchial alveolar lavage fluid (BALF) in smear-negative pulmonarytuberculosis Be worth. Methods A retrospective analysis was conducted on100 patients with clinically diagnosed pulmonary tuberculosis butnegative sputum smears admitted to Guiyang Public Health TreatmentCenter from January 2019 to July 2022. All patients had negative sputumsmears for three consecutive times and underwent fiberoptic bronchoscopyin the fiberoptic bronchoscopy room of our hospital. BALF specimens weresimultaneously tested by smear acid-fast staining, GeneXpert MTB/RIF,MTB-PCR and SAT-TB detection methods. Taking the final clinicaldiagnosis of pulmonary tuberculosis as the gold standard, the diagnosticefficiency of the three methods and cost-effectiveness analysis werecalculated. Results The positive rates of XpertMTB/RIF, MTB-PCR andSAT-TB in 100 BALF samples were 53.00%, 43.00% and 35.00%, respectively.Taking clinical diagnosis as the gold standard, the positive rates ofXpertMTB/RIF $\left({{\chi }^{2}= {21.459}, P<{0.001}}\right)$ , MTB-PCR $\left({{\chi }^{2}= {17.695}, P<{0.001}}\right)$ , SAT-TB $\left({{\chi }^{2}= {12.631}, P<{0.001}}\right)$ and clinical diagnosis were statisticallysignificant. The sensitivity of XpertMTB/RIF, MTB-PCR, SAT-TB,XpertMTB/RIF+MTB-PCR, XpertMTB/RIF+SAT-TB, MTB-PCR+SAT-TB and the threecombined detections were 64.20%, 53.09%, 43.21% and 67, respectively ${90}\%,{66.67}\%,{58.02}\%,{69.14}\%$ ; Thespecificity was ${94.74}\%,{100.00}\%,{100.00}\%,{94.74}\%,{94.74}\%,{100.00}\%$ ,94.74%, respectively. ROC analysis showed that The AUC of XpertMTB/RIF,MTB-PCR, SAT-TB, XpertMTB/RIF+MTB-PCR, XpertMTB/RIF+SAT-TB,MTB-PCR+SAT-TB and the combined detection were 0.795, 0.765, 0.716 and0.813, respectively 0.807, 0.790, 0.819. Conclusion In the rapiddetection of negative tuberculosis, it is not recommended to select theabove three tests at the beginning of diagnosis and treatment. In termsof cost effectiveness, MTB-PCR can be used as the preferred diagnosticmethod for smear-negative pulmonary tuberculosis.