To provide a superior pull-out preventive effect without enlarging an eating-in groove even in a synthetic resin fluid pipe by constituting the pull-out prevention tool to be movable with its initial eating-in state in a case of a small drawing force, and to allow the pull-out prevention tool to deeply eat-in the fluid pipe via a tapered face, when a large drawing force is applied thereon.

A pipe joint body 2 is formed of chrome steel into an approximately cylindrical shape and diameter-enlarged release prevention parts 2a preventing pulling-out of fluid pipes 3, 4 are formed in the left/right both sides with the center part in the pipe axial direction as the boundary. The release prevention part 2a defines an annular recess 8 set to a tapered presser face 7 gradually contracting its diameter toward the pulling-out direction of the fluid pipe 3 in its internal circumferential face and a claw ring 10 formed into an approximately C shape is stored therein. A plurality of presser bolts 5 are threadedly engaged in the outer circumferential face of the release prevention part 2a and each presser bolt 5 is uniformly contracted with the left end face of the claw ring 10 abutting on the annular stopper 9 so that the claw ring 10 is pressurized to provide the initial bite state.