Abstract: In a vehicle body frame structure, a bumper beam extending in the vehicle width direction, and lower members extending forwardly from the front ends of upper members, are connected to the front ends of bumper beam extensions, which are made of a fiber-reinforced resin and extend forwardly from front ends of front side frames, and the front end faces of the pair of left and right bumper beam extensions, and the front face of the bumper beam are curved into a U-shape pointing toward the front of the vehicle body. Thus, is it possible to reduce the weight of the vehicle body frame in the front part of the motor vehicle, to transmit to the bumper beam extensions a collision load inputted even into the bumper beam or inputted even into the front parts of the lower members, and to reduce the dimensions of the vehicle body front part.