Objectively, this study addresses several objectives, such as 1) identifying the existing vegetation conditions and the amount of CO concentration in the study location, 2) to investigate the ability to reduce plants to absorb CO, and 3) to projecting the absorption capacity of vegetation by CO through air prediction models. The research location was conducted at Veteran Selatan, Makassar City, Indonesia. The survey was conducted in Makassar City, Indonesia, as well as data available in the field. The research period from January to April 2020. From the analysis of the results and discussion, the conclusions drawn from this study are: 1) The CO concentration based on the calculation results is 1.186. 52 µg/m3. While the CO concentration measured in the field is 2,290.39 µg/m3, so the difference between the calculation and measurement results is 1,103,(48.2%). The number of trees as vegetation, namely 189 trees, had an enormous average volume of cover, namely 2,673.01 m3. 2). The existing plants or vegetation on exsiting location can absorb CO of 1,889.8 tons/year. 3). A balance between CO pollutants and vegetation uptake can be achieved by applying a scenario of planting vegetation for trees, shrubs, and shrubs. Modeling and simulation results show that the total CO emissions will reach 3,184.6 tons/year in the next ten years. However, by applying the planting scenario, the total CO emission in the next ten years will only reach 2,761.9 tons/year, with an average percentage reduction of 8.93%.