PURPOSE: To prevent a filler tube end part from being deformed or damaged, by providing a protector integrally to the filler tube end part, and allowing the protector to be disengaged from a car body outer plate when the car body is deformed.

CONSTITUTION: A fuel inlet 3 closed by a lid 2 is formed in the car body outer plate such as a rear fender 1 or the like, a cup-like filler base 4 is mounted to the fuel inlet 3, and a tip of a filler tube 6 sealed by a filler cap 5 is introduced into this filler base 4 via a flexible seal rubber 13. A mouth cover 7 is attached to the tip mouth of the filler tube 6, and the cup-like rigid protector 14 is integrally attached to the mouth cover 7. If the automobile collides, and the car body is deformed, the end part of the filler tube 6 is moved away from the car body outer plate.