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High-resolution spatial information extraction and pollen sensitization risk assessment of Beijing pine and cypress vegetation are of great significance for pollen concentration monitoring and prediction. Based on 304 high-resolution Sentinel-2A multispectral imager (MSI) satellite images in the winter of 2019-2020, the new enhanced normalized vegetation index (EVI) and surface water index (LSWI) are introduced to establish the method of pine and cypress vegetations extraction. The mapping of pine and cypress vegetation distribution in Beijing with 10 m spatial resolution is carried out. At the same time, using the principle of risk assessment, a spatial risk assessment method of pine and cypress pollen sensitization from the spatial distribution of pine and cypress vegetation is established. Combined with the pine and cypress pollen concentration data from the pollen observation stations in 2020, the area size and the optimal spatial distance affecting pollen concentration and the risk assessment of pine and cypress pollen sensitization are studied. The results show that based on a series of processed winter synthetic Sentinel-2A satellite images under clear weather conditions in Beijing, the vegetation of pine and cypress in Beijing can be effectively extracted by using EVI and LSWI thresholds, and the accuracy is more than 80%. The pine and cypress vegetation in Beijing is mainly distributed in the mountains in the north and southwest, followed by the northern plain, while less in the central urban area, Daxing and Tongzhou. The pine and cypress vegetation within 14 km has a positive contribution to the pollen concentration of the station, of which the pine and cypress vegetation within 6 km has the largest contribution. The relatively high-risk areas of pine and cypress pollen sensitization are mainly distributed in the northwest mountainous area, the north of Changping, the east of Mentougou, the northwest of Shijingshan and the southwest of Haidian.