To completely maintain a coupled condition of both members by inhibiting rotation of a claw member in an engagement condition, in a coupling device constituted by forming the claw member at one member, inserting and fitting to a fitting room formed at the other member by rotating the claw member.

The claw member 19 is protruded in an orthogonal direction crossing the axial direction of the other member 3 on the other member 3 side, and the fitting room 14 to which the claw member 19 can be fitted by rotating the other member 3 to rotate the claw member 19 is provided on one member 2 side. In this coupling device in which the claw member 19 is fitted to the fitting room 14 to couple both the members 2, 3 with each other, rotation inhibiting means 16, 23 are provided which inhibit the rotation of the claw member 19 under such a condition that the claw member 19 is fitted to the fitting room 14.