PURPOSE: To prevent a landslide protection wall from being deformed and broken by earth pressure, and to arrange buffer materials so that they cannot be crushed while maintaining vibration isolation effect.

CONSTITUTION: A landslide protection wall W is built underground and earth to which a foundation I of a building body is to be buried on the inside of the landslide protection wall W is excavated, and after timbering B3 is arranged against the landslide protection wall W, a support holding member 13 is attached to the face of the landslide protection wall W. Then, a holding member 12 for holding a pressure-resistant support 11 with a specified gap maintained to the landslide protection wall W to a location corresponding to the attachment position of the support holding member 13 is inserted, and the foundation 1 of the building body is made up. A buffer material 2 is provided to a space between the foundation 1 of the building body and the landslide protection wall W with the pressure resistant support 11 made to project to a specified position, being held with the holding member 12. Then, the timbering B3 that is positioned right above is dismantled. In the case where undismantled timbering B2, B1 are still existent, processes of making-up of the foundation of the building body, setting of the pressure-resistant supports, setting of the buffer materials and dismantlement of the timbering are repeated successively, and after completion of arrangement of all of the foundations of the building body and the buffer materials, the pressure-resistant supports 11 are retreated.