To provide an automobile body structure for effectively using an expanded cargo loading space by rotating an opening-closing panel to the cabin side.

When rotating the opening-closing panel to the cabin side around a lower end part of the opening-closing panel 6 arranged in the rear of a seat back 24a of a rear seat 24 in a folded state, an engaging part arranged in an upper end part of the opening-closing panel 6 is housed in a housing recessed part 24c arranged on a back face of the seat back 24a of the rear seat 24. Thus, the cargo loading space expanded toward a loading space from a rear seat part can be formed as a cargo loading space having an almost flat surface.