AbstractFirst‐principles calculations based on density functional theory (DFT‐D2 method) are adopted to systematically investigate the structure stability and sensing properties of NO and NO2 adsorbed on single nonmetals (B, C, and Si) and double nonmetals (1B1C, 1C1Si, and 1B1Si) doped blue phosphorene. The results show the chemisorption of the gas molecules absorbed on single nonmetal doped blue phosphorene with large adsorption energy, charge transfer, and small adsorption distance. Similarly, for gas molecules absorbed on double nonmetal doped blue phosphorene, while NO interaction with 1C1Si co‐doped blue phosphorene is weak. There is a strong hybridization between gas molecules and doped substrates due to the enhancing interaction, resulting in an increasing adsorption ability for gas molecules. We find that the conductivity and work function change caused by nonmetal doping is the main reason for improving the sensitivity of gas molecules, which shows more possibilities for practical gas sensor applications. Therefore, nonmetal doped blue phosphorene provides a new direction for detecting NO and NO2 in the gas sensing field.