The passive differential optical absorption spectroscopy(DOAS) system, installed in a car, was applied in the detection of pollution source of the urban area and industrial area. The gas column density was obtained by the DOAS fitting process using the zenith scattered sunlight. The distribution and transportation of SO2 , NO2 in Chongqing urban area and an industrial area of Chongqing City were achieved in the observation experiments of these areas. The influence of emission flux from this industrial area to the main city of Chongqing under the southwest, southeast wind was significant, which was 0.37 kg/s, 0.36 kg/s for SO2 and 0.29 kg/s, 0.27 kg/s for NO2 . The experimental results indicated that the mobile DOAS technology was an effective means for the detection of regional distribution and transportation of pollution gases.