A vehicle body structure includes a resin floor part provided with a flange portion bent toward an upper side or a lower side at an end in a vehicle width direction, and a metal side sill part joined to the flange portion of the floor part. The side sill part includes a rim portion, a peak portion, and intermediate portions that link the rim portion to the peak portion. The peak portion and the intermediate portions form a protruding portion projecting from the rim portion toward the floor part. The flange portion of the floor part is joined to the peak portion of the protruding portion.