To provide a geothermal exchange system having improved heat exchanging efficiency and construction property.

The geothermal exchange system has a reciprocating tube embedded in an underground for heat exchange in the reciprocating tube through a heat medium between a ground and the underground. The reciprocating tube is covered with grout, and the grout is formed of a good heat conductive and flowable material incorporating a viscose material in cement together with aggregates. Thus, heat exchanging performance and construction property are improved to actualize wide-range applications for use in heating or cooling with cold or hot air on the ground fed into the underground. The reciprocating tube is embedded in a bored well and the grout with conditioned components is filled therein, permitting easy construction and implementation.