PURPOSE: To increase the rigidity of a bumper and not to impair the external appearance even if the bumper is deflected by a method wherein a resin bumper is held and fixed at a fitting part of a bumper stay point having a wide supporting area in a car width direction.

CONSTITUTION: A main part 2 of a resin bumper 1 formed into a bumper having a section of the U letter type is coupled with a car side such as a rear side member 7 for a rear bumper through a bumper stay 5. And a bumper side 3 is fitted to a fender 9 pinchedly having a spacer 10 through a bracket 4 which is formed into one body with the bumper side 3 at its rear side. A bumper fitting part 20 is formed at the point of a stay 5 and a bolt.nut 6 is penetrated upto the rear part of the main part 2 of the fitting part 20 to connect the fitting part 20. For the fitting part 20, a wide connecting washer 21 which contacts with the upper or lower rear plane of the rear part of the main part 2 and expands to the car width direction is provided to the upper or lower part, and a supporting plane 22 which contacts with the rear plane of the main part 2 and connects to the connecting washer 21 is provided to the front part.