〔Abstract〕 Objective To analyze the etiological text results of bronchoalveolar lavage fluid (BALF) metagenomic next-generation sequencing (mNGS) on refractory pneumonia patients with traditional culture and smear negative. Methods The clinical data of 30 patients with refractory pneumonia with traditional culture and smear negative admitted to Pingtan Comprehensive Experimental Area Hospital from January to August 2022 were retrospectively analyzed. All patients had undergone mNGS examination. The traditional culture specimens were sputum, blood and BALF. The smears were sputum and BALF. All mNGS samples were BALF. The etiological results of BALF mNGS were observed and analyzed. Results mNGS 26 positive strains (86.67 %), 4 negative strains (13.33 %). 4 strains of mycobacterium tuberculosis (13.33 %), 2 strains of nocardia (7.69 %), 8 strains of caustic bacteria (30.77 %), 2 strains of anaerobic bacteria (7.69 %), 4 fungi (13.33 %) and 6 strains of atypical pathogens (23.08 %). Conclusion The traditional culture and smear negative patients with refractory pneumonia have a high positive rate of using BALF mNGS for etiological examination.