An apparatus for fixing an upper swing structure of a construction machine, the apparatus being provided to the construction machine comprising a lower traveling structure, an upper swing structure mounted to be swingable on the lower traveling structure and a working device mounted to the upper swing structure, the apparatus being configured to fix the upper swing structure on the lower traveling structure before traveling, the apparatus comprising: a protrusion formed on a lower surface of the upper swing structure and having a lower side of an outer peripheral surface configured as an inclined surface; a socket part formed on an upper side of the lower traveling structure and configured to be coupled with the protrusion in a female/male engaging manner; an elastic member; characterized in that the elastic member is arranged on a lower side of the socket part and configured to elastically support the socket part, and in that the apparatus further comprises: a first tapered member arranged on a lower side of the elastic member, configured to support the elastic member, and having a lower surface configured as an inclined surface, and a second tapered member arranged on a lower side of the first tapered member, having an upper surface configured as an inclined surface so as to make sliding contact with the first tapered member, and configured to move up the socket part to a position at which the socket part can be coupled with the protrusion or to move down the socket part so that the socket part is to be decoupled from the protrusion, through horizontal movement, a body part formed on an upper surface of the lower traveling structure, configured to accommodate therein the socket part, the elastic member and the first tapered member, and having an upper end opened so as to enable the socket part to move up and down and a lower end of which both sides in a horizontal direction are opened so that the second tapered member can be inserted therein, wherein the first tapered member is restrained from moving in the horizontal direction by the body part. a protrusion formed on a lower surface of the upper swing structure and having a lower side of an outer peripheral surface configured as an inclined surface; a socket part formed on an upper side of the lower traveling structure and configured to be coupled with the protrusion in a female/male engaging manner; an elastic member; characterized in that the elastic member is arranged on a lower side of the socket part and configured to elastically support the socket part, and in that the apparatus further comprises: a first tapered member arranged on a lower side of the elastic member, configured to support the elastic member, and having a lower surface configured as an inclined surface, and a second tapered member arranged on a lower side of the first tapered member, having an upper surface configured as an inclined surface so as to make sliding contact with the first tapered member, and configured to move up the socket part to a position at which the socket part can be coupled with the protrusion or to move down the socket part so that the socket part is to be decoupled from the protrusion, through horizontal movement, a first tapered member arranged on a lower side of the elastic member, configured to support the elastic member, and having a lower surface configured as an inclined surface, and a second tapered member arranged on a lower side of the first tapered member, having an upper surface configured as an inclined surface so as to make sliding contact with the first tapered member, and configured to move up the socket part to a position at which the socket part can be coupled with the protrusion or to move down the socket part so that the socket part is to be decoupled from the protrusion, through horizontal movement, a body part formed on an upper surface of the lower traveling structure, configured to accommodate therein the socket part, the elastic member and the first tapered member, and having an upper end opened so as to enable the socket part to move up and down and a lower end of which both sides in a horizontal direction are opened so that the second tapered member can be inserted therein, wherein the first tapered member is restrained from moving in the horizontal direction by the body part.