Utilizing green wall plants to absorb CO2 is one of the effective means to achieve carbon sequestration in buildings. However, the carbon absorption and indoor environmental regulation capabilities of different plant types still need further understanding. Therefore, this study selected three common indoor plants as research subjects, using a closed measurement method and controlled variable approach to compare the carbon dioxide absorption capacity of three common indoor plants and their regulatory impact on the indoor thermal and humidity environment. By using the unit leaf area method to quantify the impact of plants, the study obtained the CO2 absorption, humidity release, and temperature difference values per unit leaf area for each plant under the same environment. Through comparison, it was found that the Epipremnum aureum has an outstanding performance in CO2 absorption, while the Chlorophytum comosum shows a higher humidity release capability. The Epipremnum aureum 's CO2 absorption rate is 0.39g/d·m2, 1.2 and 1.34 times higher than the Philodendron and Chlorophytum comosum. The Chlorophytum comosum 's humidity release is 94.59g/kg·d·m2, 1.4 and 2.9 times more than the Philodendron and Epipremnum aureum. Based on this, a typical household was used as an example to design a green wall and calculate its carbon absorption potential. The study not only provides new quantitative indicators for the assessment of the carbon sequestration capacity of green walls but also offers new perspectives and references for the application of building carbon sequestration technology.