The invention relates to a device in the form of a perforating trocar and is intended in particular to be used for surgery and interventional radiology. The device comprises an outer sleeve (5) having a rigid tube (8), and a mandrel (6) having a rod (18). The rod (18) is suitable for sliding in the outer sleeve (5) and has, at its distal end, a perforating tip (21, 33). The rod (18) additionally has a longitudinal groove (20) arranged on the surface of the rod (18), and extending from the distal end to the proximal end of the rod (18), in order to allow the device to slide on a guide pin.