The utility model discloses an automatic calibration apparatus of a current vortex sensor for measuring a TBM hobbing cutter wear extent. The automatic calibration apparatus is characterized in that convex guide rails arranged at two sides of a base plate cooperate with concave grooves formed at hobbing cutter supports. A rolling leading screw shaft coupling connects a left rotating lead screw and a right rotating lead screw to form an integrated one. With the rotating lead screws, the hobbing cutter supports are driven to move at opposite directions by facing each other or with back to each other, so that the distances between the hobbing cutter supports are suitable for installation of hobboing cutters with different dimensions. A shaft of a hobboing cutter is embedded into fixed blocks and is installed in the semicircular grooves of the hobbing cutter supports. A single-chip microcomputer controls a drive circuit; the motor drives a sensor lead screw to rotate; and the distance between a sensor standing plate moving at the T-shaped guide rail and the hobbing cutter blade is changed, so that the wearing process of the hobbing cutter is simulated. A voltage signal outputted by a current vortex sensor and a distance signal outputted by a displacement sensor are sent into a conditioning circuit; after conditioning, the signals are sent into the single-chip microcomputer for processing; and then a fitting coefficient of the hobboing cutter wear extent is obtained by fitting and the data are displayed.