Many previous studies have investigated aerodynamics and deposition effects separately and have mainly considered the effect of urban buildings on air circulation. In this study, a simplified model was developed based on the quantification of the aerodynamic effects of dry deposition of pollutants, in which the components of street trees were added to analyze the aerodynamic effects of street trees on pollutant concentrations. The model can be used to evaluate the effects of different tree planting scenarios on pollutant removal. The theoretical model suggests that the pollutant deposition mass flux is nonlinearly correlated with the tree canopy cover area and increases with the tree canopy cover area until it reaches a critical point. The critical point is when the tree canopy cover area reaches around 90% of the neighborhood area excluding the building footprint. Future scenarios showed a reduced pollutant deposition mass contributed by urban trees, demonstrating the need to consider urban tree management and its impacts on pollutant removal. All tree planting scenarios demonstrated positive pollutant deposition mass fluxes, ranging from a continuous increase in tree area from existing tree cover conditions to the NYC plan of 30% coverage. Under the Million Trees NYC initiative in New York City, this research verified the feasibility of the goal from the pollutant deposition perspective and explored potential optimized tree planting options, hoping to provide a reference for city planners.