Abstract: An earth cooling system, which makes use of the soil around an underground tunnel as a cool source to cool the ventilation air of animal house, has the good performance on cooling with a lower energy consumption and a long service life, and can be managed and maintained easily. This system also can be used for heating the ventilation air of animal house in winter. The problem exist that its construction cost is higher, however. Some possible ways to reduce its construction cost and to receive more benefit from it were presented in this paper. 