The embodiment of the invention provides an instrument intervention device and system, and belongs to the technical field of medical instruments. The instrument intervention device comprises an imagepoint cloud module, a real-time point cloud module, a point cloud registration module, a real-time error module, an intervention safety line module and an output module; and through mutual connectionand cooperation of the modules, the real-time error and an intervention safety line of registration of an image point cloud and a real-time point cloud are calculated, and when the real-time error islower than the intervention safety line, an intervention signal is output outwards, so that a medical worker performs the intervention process of instruments. The opportunity of instrument intervention can be determined on the basis of the position relation between the body surface of a human body at a certain moment and a target area, and the dependence on artificial experience during intervention opportunity judgment is avoided.