This paper reviews effects of CO₂ enrichment in atmosphere and roots media on growth, yield, quality and some other physiological characteristics of tomato, and interactive effects of environmental factors and CO₂ on tomato. CO₂ enrichment increased the tomato's growth, yield, quality and photosynthesis. Respiration and transpiration of the plant and incidence of insects and diseases decreased under elevated CO₂. Environmental factors affected the responses of tomato to CO₂ enrichment. It was suggested that later researches should be focused on nutrient absorption characteristics of tomato under elevated CO₂.