To eliminate the necessity of mounting "a hydraulic unit comprising a valve mechanism for a pile punching machine" on a hydraulic shovel body by improving a pile punching machine of the type with an exciter 4 and a chuck 5 mounted on a hydraulic shovel 1.

A valve mechanism 12A for controlling the exciter 4, and a valve mechanism 12B for operating the chuck 5 are installed at an extension 2. Preferably, the extension 2 is formed as a box type to enclose the valve mechanisms 12A, 12B to make protection of the valve mechanisms perfect. When the exciter, chuck and extension are detached to perform work other than pile punching, the pile punching valve mechanism is detached from the hydraulic shovel following the detachment and does not get in the way of other work.