By the impact of urban expansion, industrial development and increased car ownership, air particulate matters have been becoming the primary pollutant in many cities. As the largest and unique ecological system with a self-cleaning function in urban ecological construction, the urban forest not only provides a relatively clean recreation space for residents in the city under the polluted environment, but also plays an important role in purifying the pollution of air particulate matter. In this paper, the regulating function of urban forests was explicated from several aspects including regulation mechanism, analysis method, and functional variation and spatial-temporal variation pattern of different individuals and urban forest types in regulating the air particulate matter. Results indicated that: there have been relative more studies on regulation mechanism involving in physical dustfull while the study on chemical cleaning of dust is lack; Application of the weight method for determining of vegetation dust retention draws more attention while study on the concentration method application for purifying air particulate matter of the environment in urban forest is relatively less. In the near future, the processes and mechanism of chemical dust-removal by forests, and all-around regulating effects of urban forests should be systematically studied, and transformation and practical application of the research findings will be an important direction.