This paper presents a description, verification, and application of a model simulating the transport of aerosol particles with different properties in the urban boundary layer by using a Lagrangian approach. The model takes input fields of air flow characteristics from arbitrary external models or analytical solutions and allows estimating the movement, sedimentation, and decay of particles. In this paper, the accuracy of the model is successfully estimated on the basis of exact analytical solutions. Simulations are made for a series of urban canyons under different conditions of stratification and wind speed to assess the effects of these meteorological parameters on particle transport in urban areas. Under similar conditions, the transport of particles simulating SARS-CoV-2 coronavirus particles is calculated.