Abstract: In order to reveal the evolution of air pollution and promote the continuous improvement of air quality, a three-dimensional observation network was established in the Beijing-Tianjin-Hebei and its surrounding areas to address the core scientific issues about the occurrence, evolution and dissipation of heavy air pollution. In the autumn and winter of 2017, the spring, autumn and winter of 2018, ground-based remote sensing of heavy pollution periods and processes autumn and vehicle-mounted navigation observations were carried out to evaluate the regional air pollution transport and the mutual spread of air pollution between cities. The results showed that the pollution in Beijing had obvious regional characteristics: in spring, it was mainly affected by the unfavorable regional diffusion conditions and dust transport; in autumn, it was mainly affected by the southwest channel transmission; in winter, it was mainly affected by the transport in the mixed layer of southwest, southern and southeast channels and regional diffusion conditions. In autumn and winter, the NO₂ and SO₂ pollutants in the Beijing-Tianjin-Hebei Region were lower than those in the southwest, southeast and southern transmission channels, and Beijing City was easily affected by the transportation of pollutants when the steady weather conditions of weak southerly wind dominated. According to the research, among the transport channels of various scales of foreign pollutants in Beijing, the southwest of the boundary layer was the main transport pathway, followed by the southeast and east channels.