PURPOSE: To obviate the needs to chip extra-branking concrete formed on the head of a pile by a method in which an iron bar cage is set in the hole of the pile, concrete is placed to the bottom level of a footing, a connecting precast pile is inserted, and then the footing is cast on the connecting precast pile.

CONSTITUTION: A pile pit 1 is drilled, an iron bar cage 2 is set in the hole, and concrete 3 is placed to a level L corresponding to the bottom of a footing. Then, an excavating casing is drawn out, a connecting precast pile 5 is vertically inserted into the center of the uncured concrete 3 in the pit 1, and then a hung rope 6 provided on the upper end of the precast pile 5 is coupled with a supporting bar 7. Soil on the level L is removed, the top sides 8 and 9 are chipped horizontally, formwork is set for footing, concrete 10 is placed into the formwork and hardened, and then soil G1 is back filled. Thus, since loads are all burdened by the pile 5, extra-banking faulty concrete C plays a role on safety side and thereby the need for chipping the concrete is eliminated.