To simply and easily fix a structure part such that a throttle valve operation cable to operate a throttle valve for engine intake control has a slight backlash in a state that a throttle valve is in a closed state.

The end part of the sheath 16 of a throttle valve operation cable 15 is securely inserted and a holder 27 in which the end part of a wire 17 is inserted is inserted in the insertion hole 30 of the bracket 29 of a structure part, and the large screw lever 22 of a holder 27 and the large and small mounting holes 33 and 34 of the insertion hole 30 are respectively engaged. The neck part 21 of the holder 27 is grasped by a tool and screwed in a given position only through operation of one hand. One of two mounting holes 33 and 34 forms a threadless hole of synthetic resin and one of two screw levers 22 and 23 is threaded and through engagement therebetween, fixing is practicable without loosening.