A connection structure, for connecting a power cable and a conductor lead-out rod, which connects a conductor part including a plurality of wires of a power cable to a conductor lead-out rod of a termination connection box, the connection structure comprising: a conductor part of a power cable; an adapter configured into which the conductor part is inserted through an open lower end thereof, the adapter being formed in a cylindrical shape, an upper end and the lower end of which are open; a conductor lead-out rod comprising: a body part providing an accommodation groove which has an opening in a lower end thereof and into which an upper end of the conductor part of the power cable inserted into the adapter is inserted; and an extension extending upward from an upper end of the body part, and a plurality of conducting fastening holes that are provided in an upper portion of the body part at predetermined intervals in a circumferential direction, and a plurality of fixing fastening holes that are provided in a lower portion of the body part at predetermined intervals in the circumferential direction; a plurality of conductive particles injected into an accommodation space on an upper end of the conductor part inserted into the accommodation groove of the conductor lead-out rod to electrically connect the conductor part and the conductor lead-out rod; a plurality of conducting bolts configured to be fastened into the plurality of conducting fastening holes to apply pressure to the conductive particles injected into the accommodation space so as to electrically connect the conductor part and the conductor lead-out rod; and a plurality of fixing bolts configured to be fastened into the plurality of fixing fastening holes to fix the conductor part inserted into the accommodation groove, wherein the plurality of conducting fastenings holes and the plurality of fixing fastening holes are alternately formed in a direction perpendicular to the body part. a conductor part of a power cable; an adapter configured into which the conductor part is inserted through an open lower end thereof, the adapter being formed in a cylindrical shape, an upper end and the lower end of which are open; a conductor lead-out rod comprising: a body part providing an accommodation groove which has an opening in a lower end thereof and into which an upper end of the conductor part of the power cable inserted into the adapter is inserted; and an extension extending upward from an upper end of the body part, and a plurality of conducting fastening holes that are provided in an upper portion of the body part at predetermined intervals in a circumferential direction, and a plurality of fixing fastening holes that are provided in a lower portion of the body part at predetermined intervals in the circumferential direction; a plurality of conductive particles injected into an accommodation space on an upper end of the conductor part inserted into the accommodation groove of the conductor lead-out rod to electrically connect the conductor part and the conductor lead-out rod; a plurality of conducting bolts configured to be fastened into the plurality of conducting fastening holes to apply pressure to the conductive particles injected into the accommodation space so as to electrically connect the conductor part and the conductor lead-out rod; and a plurality of fixing bolts configured to be fastened into the plurality of fixing fastening holes to fix the conductor part inserted into the accommodation groove, wherein the plurality of conducting fastenings holes and the plurality of fixing fastening holes are alternately formed in a direction perpendicular to the body part. a body part providing an accommodation groove which has an opening in a lower end thereof and into which an upper end of the conductor part of the power cable inserted into the adapter is inserted; and an extension extending upward from an upper end of the body part, and a plurality of conducting fastening holes that are provided in an upper portion of the body part at predetermined intervals in a circumferential direction, and a plurality of fixing fastening holes that are provided in a lower portion of the body part at predetermined intervals in the circumferential direction; a plurality of conductive particles injected into an accommodation space on an upper end of the conductor part inserted into the accommodation groove of the conductor lead-out rod to electrically connect the conductor part and the conductor lead-out rod; a plurality of conducting bolts configured to be fastened into the plurality of conducting fastening holes to apply pressure to the conductive particles injected into the accommodation space so as to electrically connect the conductor part and the conductor lead-out rod; and a plurality of fixing bolts configured to be fastened into the plurality of fixing fastening holes to fix the conductor part inserted into the accommodation groove, wherein the plurality of conducting fastenings holes and the plurality of fixing fastening holes are alternately formed in a direction perpendicular to the body part.