Abstract: As one of the most important air pollutants, tropospheric ozone (O₃) has great impacts on morphological characteristics and physiology and biochemistry of plants, and thus further changes global and regional carbon cycle, climate and environmental conditions. In the present study, the authors first systematically review the previous studies of site-level observations concerning the impact of O₃ on vegetation, including photosynthesis, stomatal conductance, leaf area, and yield or biomass. Advantages and disadvantages of existing ozone exposure indices and parameterization schemes are then analyzed. In addition, the authors introduce the use of these parameterization schemes in global dynamic vegetation models and earth system models, and their application in quantifying the O₃ impact in the Earth system. Finally, the authors discuss the problems in the existing studies and provide suggestions for further development.