Air pollution in urban environments is a major problem for residents of large cities. The main cause of pollution is the presence of many cars that emit harmful substances directly at the human level, which seriously impacts the health of urban residents. Based on the numerical solution to the problem of pollution propagation in the urban environment, conclusions are drawn about the concentrations of carbon monoxide near the central streets of Kharkiv. The problem was solved by solving the Reynolds-averaged Navier-Stokes system of equations, the impurity transport equation, the continuity equation, and the turbulence model equations. The study was carried out in three stages: In the first stage, a three-dimensional model of the central part of Kharkiv was prepared. In the second stage, the model was verified and validated by comparing it with experimental studies of air velocity at certain points. In the third stage, the mathematical model was solved by considering the transport of impurities. The modeling was carried out with winds of different directions. The wind-averaged flow patterns showed certain city streets with the highest concentrations of carbon monoxide. The study results will make it possible to formulate ways of further solutions to the environmental and urban problems of the city of Kharkiv.