In response to the technological requirements for miniaturized, multi-angle, multi-altitude, and rapid simultaneous acquisition of atmospheric pollutants, this study has developed an integrated, lightweight, and cost-effective airborne Differential Optical Absorption Spectroscopy (DOAS) system. This system is designed to be used on a rotorcraft unmanned aerial vehicle (UAV) platform for monitoring atmospheric pollutants. The composition of the hexacopter UAV platform and the airborne DOAS system is detailed in this paper. The system includes a MAX-DOAS spectral acquisition system, a control system, and a flight environment monitoring system. Commands are sent from a computer via serial communication to drive a gimbal, controlling the azimuth and elevation angles of the telescope, with a camera recording the light obstruction. The sunlight scattered by the atmosphere is collected by the telescope and transmitted via fiber optics to the spectrometer, which then transmits the data to the control computer. Additionally, the system captures data on altitude, temperature, humidity, and GPS location during flight, filtering out spectral data under abnormal flight conditions. Stability studies indicate that the mean angular deviations for yaw, roll, and pitch are 0.07°, -0.13°, and -0.12° respectively, meeting the requirements for monitoring stability. Comparative experiments with a commercial ground-based DOAS system show that the correlation coefficients between the monitoring data of both systems are greater than 0.92, confirming the reliability of the airborne system. During field flight experiments, the airborne DOAS system conducted observations at altitudes of 30m, 60m, and 90m, with the elevation angle set at 0° and the azimuth angle measured every 30° from 0° to 360°. The system successfully obtained the concentration distribution of NO ₂, SO ₂, and HCHO at different azimuth angles and altitudes. The results indicate that the concentrations of all three gases decrease with increasing altitude, with higher concentrations observed in the southeast direction, suggesting the presence of pollution sources in that direction. Further analysis considering altitude changes revealed that the rate of concentration decrease for NO ₂and SO ₂slows with increasing altitude, while the decrease rate for HCHO remains relatively constant. The findings demonstrate that this system effectively meets the technical demands for simultaneous rapid multi-angle and multi-altitude detection of atmospheric pollutants, providing essential support for detailed monitoring in complex urban micro-environments.