Green belts along roads can purify the air and improve the air quality along the roads. The microclimate conditions around a road will affect the manner and speed of pollutant diffusion, and it may affect how effective the green belt is in removing pollutants from the air. In this study, the effects of microclimate conditions on the removal of pollutants by green belts along roads were monitored, and the results will provide a basis for improving the road environment by improving our understanding of the manner in which the air around roads is purified by green belts. Microclimate conditions (wind speed, air temperature, relative humidity in the air, surface temperature, and air pressure) and the concentrations of five major pollutants, SO₂, NO_x, NH₃, total suspended particles (TSP) and respirable particulate matter (PM₁₀), were observed along 18 roads with green belts in the city of Taiyuan. The meteorological elements correlated with each other along the Taiyuan roads in the summer. There were significant positive correlations between the wind speed and the surface temperature, and the air and surface temperatures also significantly positively correlated. However, the relative humidity, the surface temperature, and the air temperature were significantly negatively correlated. In most cases, the average pollutant concentration caused by non-motorized vehicles when a green belt was present was lower than the average pollutant concentration caused by non-motorized vehicles when a green belt was not present, so the green belt appeared to play a role in removing pollutants from the air around the road. The percentages of the concentrations of the five pollutants that were removed by the green belt had significant regression coefficients with the meteorological factors. Regression equations, and the statistical significances of the regressions, were established for the relationships between the pollutant removal percentages and the meteorological factors, but different pollutants were affected by different meteorological factors. The SO₂ removal percentage was mostly affected by the wind speed and air temperature, the percentage removed increasing with both meteorological conditions. The NO_x removal percentage was mainly affected by, and increased with, the ground temperature. The NH₃ removal percentage was mainly influenced by, and increased with, the air temperature. The TSP removal percentage was mainly affected by, and increased with, the air humidity. The PM₁₀ removal percentage was mainly affected by, and increased with, the air temperature and air pressure. Green space regulates, to a certain extent, the surrounding microclimate, and can cause the air temperature to decrease and the air humidity to increase in the summer. A decrease in air temperature around the road will decrease the rate of vertical diffusion of NO_x, NH₃, and PM₁₀, but an increase in air humidity will promote a decrease in TSP concentrations around the road. In future ‘green’ road designs, an appropriate increase in the road green belt area will be beneficial in both improving the road microclimate environment and in decreasing the concentrations of solid contaminants (TSP) in the air. However, it will probably not be effective in improving the diffusion of NO_x, NH₃, and PM₁₀. Weather conditions will affect the pollutant removal percentages achieved by green belts along roads, so more meteorological studies need to be conducted along road green belts to provide the information needed to improve our ability to achieve pollutant removal using green belts along roads in urban areas, and to improve road construction planning.