The invention discloses a geothermal 
resource development system and method using a multi-
branch radial horizontal well, and relates to the field of 
geothermal energy development and utilization. Thegeothermal 
resource development system comprises a main well section, at least one horizontal well section, a 
heat pipe unit and a ground heat exchange 
system, wherein the lower end of the main well section is located on a geothermal rock reservoir; the horizontal well sections are arranged on the side wall of the lower end of the main well section; the 
heat pipe unit comprises at least one firstheat 
pipe and a second 
heat pipe, the first heat pipes are arranged in the horizontal well sections, the second heat 
pipe is arranged in the main well section, and one ends of the first heat pipes extends to the main well section for heat exchange with the lower end of the second heat 
pipe; and the ground heat exchange system comprises a ground heat exchange device for heat exchange with the upperend of the second heat pipe, a heat exchange device and a drive pump, the ground heat exchange device, the heat exchange device and the drive pump are in communication with one another to form a circulation pipe line. The 
heat transfer efficiency can be effectively improved, the 
energy loss rate in the transmission process is reduced, and the transmission of large heat under small 
temperature difference can be realized.