Abstract: Under natural diffusion condition, the CO₂ concentration along the vegetable growing area of plant and animal complementary ecosystem is uneven. The ratio of plant growing area to animal raising area varies greatly in the present system that causes CO₂ too high or too low. These two problems are revealed in this paper by experiments. A CO₂ transferring installation composed of propeller fan and perforated film duct and an underground heat exchange system combining CO₂ transfering function are designed and tested. The two methods possess a high effect on the promotion of vegetable production.