Ground-coupled heat pump systems quickly attract attention in the world by the advantages of energy saving and no-pollution to the environment as a hot research topic. The efficiency heat exchanger of the heat transfer is always one of the main problems of the ground source heat pump technology research. Comparing with the traditional single U-shaped, the taking heat conditions of coaxial casing-shaped were also studied, and the experimental study of the collected data were discussed which explained good heat transfer effect.