To provide a pile rotatively penetrable without being stressed on its main body and joint part due to distortion and a penetration apparatus.

A pile has an inner space for inserting a rod therein, and its base end side exposed from the ground can be jointed with a pile having the same cross-sectional shape. The rod can be fitted to the pile at an optional depth inside the inner space of the pile. A penetration apparatus is mounted with the rod and fits the pile to the rod at the tip of the pile and at a joint part to rotatively penetrate the pile into the ground.