To provide a tightening bolt set capable of preventing a washer and a nut from turning together, preventing a bolt from turning when tightening them and controlling a torque to a predetermined value.

This tightening bolt set is constituted such that both tightening members 71, 72 can be firmly connected, the set includes the bolt 4, the nut 6, and the washer 5, the bolt 4 is provided with a bolt head 41 coming into contact with the tightening member 71 on one side and a shank 42 inserted into the tightening member 72 on the other side and extending, the shank 42 is provided with a connection part 421 connected with the bolt head 41 and a screw part 22 screw-fitted in the nut 6, the washer 5 is provided with both side faces 51, 52, many projections 53 arranged radially at equal interval are provided in a peripheral fringe part of the side face 51 on one side coming into contact with the tightening member 72 on the other side, and the bolt 4 is first inserted in both tightening members 71, 72, the washer 5 is inserted therein, then the nut 6 is screw-fixed to the bolt 4 by a tool 8, and the tightening member 72 on the other side is pressed by the nut 6 through the washer 5 to bring both tightening members 71, 72 into firm contact when connecting both tightening members 71, 72 firmly.