Provided is an implant apparatus having a strong coupling structure between an abutment and a zirconia cap. The implant apparatus includes: a fixture that is fixed to an alveolar bone that is placed in an area from which a tooth has been lost an abutment that is coupled on top of the fixture and on the outer surface of which at least one coupling protrusion is formed a zirconia cap on the inner surface of which at least one coupling groove is formed in correspondence to the at least one coupling protrusion of the abutment and that is fixedly coupled so as to surround the outer surface of the abutment a fixing screw that secures the zirconia cap coupled with the abutment to the fixture and an artificial crown that is fixedly coupled with the upper portion of the zirconia cap.
