PURPOSE: To easily settle and construct a composite pile by a method wherein a concrete pile is inserted into a steep pipe, they are driven in place, and then the pile alone is driven to a given depth so as to combine the pile and the steel pipe integrally.

CONSTITUTION: A concrete pile 2 is inserted into a steel pipe 3, an auger rod 5 is turned by a motor 4, soil and sand are excavated by an expandible bit 6, and the steel pipe is driven. When the steep pipe 3 reaches a given first depth, the steel pipe alone is fixed at the position, other pile 2' is connected to the pile 2, and these piles 2 and 2' alone are driven by rotating an auger rod 5. Then, a hardening agent is injected into an aperture between the piles 2 and 2' and the excavated pit and then cement milk is injected into the space formed by the piles 2 and 2', the steel pipe 3, and a separator 10 so as to integrally combine the piles 2 and 2' and the steel pipe 3.