The invention relates to the technical field of fastening tools, and discloses a bolt fastening tool for a back surface of a pipe fire resistance ring for a building. The bolt fastening tool comprisesa fixing tool main body, a driving hydraulic block, a hydraulic rod, a driven hydraulic block, a driven gear and a main body handle, wherein the fixing tool main body comprises a main body shell, anupper operating block, a fixed table, a sliding table, a sliding groove, a rotating bolt, a rotating table and a fixing bolt, the main body shell is a cuboid, a cuboid hole is formed in the right surface of the main body shell, the upper operating block comprises an upper operating block shell, a driving hydraulic groove, a driven hydraulic groove, a rotating hole, a rotating column and a tooth sliding groove, the upper operating block shell is a cuboid, the rotating hole is a circular hole, the rotating hole is formed in the rear end of the upper surface of the upper operating block shell, the size of the main body handle is the same as that of the rectangular hole formed in the right surface of the main body shell, a hand-held hole is formed in the right end of the surface of the main body handle, and the handheld hole is a rectangular hole. The bolt fastening tool achieves the purposes of being labor-saving and capable of being used in various situations.