To efficiently prevent the near-ground surface part of a strut to be buried near the surface of a ground from being rusted by efficiently fixing a heat-shrinkable tube to the near-ground surface part.

This device 1 for manufacturing a strut buried near the surface of a ground includes a support member 3 for horizontally supporting a strut 2 to be buried near the surface of the ground, a heat supply part 4 for supplying heat radially to the outside of the strut 2, and an inside heat supply part 5 for supplying heat lower in temperature than the heat from the heat supply part 4 to the inside of the strut 2. The heat is supplied from the inside heat supply part 5 to the inside of the strut 2, the strut 2 is inserted into a cylindrical heat-shrinkable tube 6 with a larger diameter than the strut 2, and while both ends 6a, 6b of the heat-shrinkable tube 6 are held by spacers 7, the heat-shrinkable tube 6 is heated and shrunk by the heat supplied from the heat supply part 4 to fix the heat-shrinkable tube 6 to the near-ground surface part 2a of the strut 2.