There is provided a vehicle body structure, including: a die-cast rear floor side member; and a metal rear floor side member rear, a joint section including: an inner joint section provided at a side of the rear floor side member, the inner joint section including at least three joining faces including an upper face provided at an upper portion, in a vehicle vertical direction, of the inner joint section and two faces positioned with orientations intersecting the upper face in a cross-section profile of the inner joint section sectioned along the vehicle vertical direction and the vehicle width direction, and an outer joint section provided at the side of the rear floor side member rear, the outer joint section abutted against and joined to the three joining faces of the inner joint section from an outer side of the inner joint section.