Anti-interference device for construction machine

Detecting section detects joint angles and the relative angle of rotation from a plurality of rotatable operating tools mounted on a single mobile platform of a construction machine. Interference distance calculator, having recorded predetermined point positions for each operating tool, derives the distances between the plurality of operating tools on the basis of the detection results and the point positions, and calculates the shortest approach distance from these distances. If this shortest approach distance is less than a prescribed set distance, anti-interference controller issues a warning to alarm via the output controller, and it outputs anti-interference control to hydraulic control section CC such that the approaching tool is halted or slowed down, or the velocity of the operating tool being approached is matched to that of the approaching tool depending on the set mode.