The invention relates to a device for providing assistance in otologic surgery of a patient who is to be implanted with a cochlea implant, the device comprising:means for identifying the positions of an entry point (21) on the surface of the cochlea and of a control point (20) in the sinus tympani, these position-identification means being operable via the external auditory canal；processor means (100) to respond to the coordinates of said points to determine a straight-line path (T) passing through those two points and defining a docking point (22) on the outside surface of the mastoid bone； anddrilling means (25, 27) for drilling a passage up to the cochlea through the mastoid bone along said straight-line path, so as to create a passage up to the cochlea.
