To provide a method and structure for burying a ground heat exchanger tube that can sufficiently use ground heat, has no risk of damage to a heat exchange tube, and is easy in the replacement and maintenance of the heat exchanger tube.

A tubular network 3 that is a tubular molding of three-dimensionally meshed threads of thermoplastic resin having voids connecting inner and outer surfaces is buried with a space to surround a heat exchanger tube 2 to be buried, and the heat exchanger tube 2 is inserted into the tubular network 3. Groundwater A passing through the meshes of the tubular network 3 flows freely in the space surrounding the heat exchanger tube 2 and contacts with the heat exchanger tube 2 over a wide contact area, thus enhancing the efficiency of heat exchange with the groundwater A to sufficiently use ground heat. The tubular network 3 can prevent the surrounding ground from being collapsed to protect the heat exchanger tube 2 from damage and facilitate the replacement and maintenance.