The invention provides a cable hole blocking apparatus. The cable hole blocking apparatus comprises fireproof partition plates and a fireproof supporting plate; the section of the fireproof supportingplate is semicircular annular; the fireproof supporting plate is used for supporting a cable, so that the cable does not apply force on the subsequently filled fireproof blocking material, falling off of the fireproof blocking material caused by stress can be avoided, and high sealing performance of the subsequently filled fireproof blocking material is ensured; the number of the fireproof partition plates is two, and the section of each fireproof partition plate is sector-ring-shaped; the central angle of the fireproof partition plates is greater than 90 degrees; the two fireproof partitionplates are rotationally connected with the two ends of the fireproof supporting plate, so that superposition between the center of circle of the section of the fireproof supporting plate and the center of circle of the section of the two fireproof partition plates can be prevented; the fireproof supporting plate and the two fireproof partition plates are matched to form a cavity for allowing the cable to pass through; the fireproof partition plates are rotated to form an opening between the two fireproof partition plates, so that the cable can be put in and taken out conveniently; the cable can be fixed by closing the two fireproof partition plates; and therefore, the blocking apparatus can be detached and assembled very conveniently, without damaging the cable.