To provide a device capable of being treated safely and surely even at a dangerous place, where a man is difficult to approach, and even in works requiring power more than manpower.

The crane front-end working device has a boom head bracket freely mounted and demounted to and from a boom head as the front end of a crane and a robot installed to the boom head bracket 110. The robot consists of a base rotatably connected to the boom head bracket 110 in a vertical surface, a slewing post 160 freely rotated on the base, a connecting arm 170 tuned in the vertical surface, being freely folded and set up to the slewing post 160, an attachment mounting base 180 freely revolved in the vertical surface at the front end of the connecting arm 170 and a base-attitude holding rod 190 freely expanded and contracted to the base at that time.