[Background] Nitrogen oxides (NOX) are among the first major air pollutants to be regulated in China, and plants play an important role in their atmospheric NOX removal. However, whether phyllosphere microorganisms can enhance the efficiency of atmospheric NOX removal remains an open question. Therefore, the isolation and screening of phyllosphere microorganisms with high NOX conversion efficiency are of great significance. [Methods] In this study, a nitrogen oxide-selective enrichment culture method was used to isolate and screen a functional strain with high NOX conversion efficiency from the phyllosphere of Hedera helix, designated as strain LZY1. The taxonomic classification of this strain was determined through 16S rRNA gene sequencing and physiological and biochemical identification. Additionally, its growth conditions (temperature, pH) were optimized, and its NOX conversion capacity was assessed. Furthermore, an exposure experiment was conducted to verify the strain’s ability to reduce atmospheric NOX. [Results] The results showed that strain LZY1 could grow using nitrogen dioxide (NO2) as its sole nitrogen source. 16S rRNA gene sequencing revealed that this strain was most closely related to Priestia flexa (100% similarity) . The strain exhibited a colony diameter of<1 cm, no swollen sporangia, and possessed nitrate reduction ability, catalase activity, motility, citrate utilization, and gelatin liquefaction capability. However, it did not undergo the Voges-Proskauer (VP) reaction and lacked anaerobic growth capability, consistent with the metabolic characteristics of Priestia flexa. The optimal growth conditions for strain LZY1 were 30℃ and pH 4. 0-6. 0, with the ability to grow within a broad pH range (4. 0-9. 0) . The exposure experiment demonstrated that this strain significantly accelerated the reduction of atmospheric NO2 concentration compared to the control group. [Conclusion] Strain LZY1, isolated from the phyllosphere of Hedera helix, exhibits a high efficiency in converting atmospheric NOX and demonstrated strong environmental adaptability. These findings provide a reference for the bioremediation of NOX-polluted air and offer new insights into atmospheric pollution control.