The present invention relates to an implant-abutment comprising: a fixture, which is coupled to an alveolar bone and comprises on the inside thereof a female tapered part having a tapered shape; an abutment, which has one side comprising a male tapered part, which has a shape corresponding to the female tapered part so as to be coupled to the female tapered part in an engaging manner, and the other side having a prosthesis coupled thereto; and an elastic part provided between the female tapered part, and the male tapered part so as for the abutment to move between a locking position, in which the abutment stays coupled to the fixture and is inhibited from moving away from the alveolar bone, and a sinking position, in which the abutment moves and sinks toward the alveolar bone by the occlusal force of occluding teeth. Configured as such, the present invention allows slight movement under a predetermined external, force by the occlusal force of teeth while stably maintaining the state of being coupled to the fixture and allows the abutment to be separated and easily retrieved from the fixture, if necessary, by the application of an external force equal to or greater than a target coupling force whereby the fixture and abutment stay coupled.