The constant challenges associated with metal oxide semiconductor (MOS) gas sensors, such as high operating temperature, low gas-sensing response, and prolonged recovery time towards NO2 restrain their practical application. Herein, we put forward a novel thought via utilizing the synergistic interplay between La doping modification and chip rapid heating treatment to solve these drawbacks. Wherein, the 3 at% La-doped SnO2 nanospheres treated at 200℃ by rapid chip heating (referred to as 3LS-200 NSs) exhibited exceptional performance. At room temperature, these nanospheres demonstrated a highly sensitive response of 3008–20 ppm NO2 within a rapid response time of 9 seconds. Furthermore, this sensor exhibited a low detection limit of 200 ppb and long-term stability. The oxygen vacancy content of 3LS-200 NSs increased by 10.8 % compared with that prepared by normal heating treatment (3LS-200NH NSs) with slow heating rate. The exceptional gas sensing properties of 3LS-200 NSs towards NO2 can be primarily attributed to the increase of oxygen vacancies, resulting in a reduced bandgap and the Fermi level shift of 0.07 eV toward the conduction band edge, hence enhancing surface electron transfer capability. This work presents a simple and energy-efficient strategy for commercial NO2 detection.