To provide a floor board structure for automobile, which allows the efficient and wide utilization of the floor section space.

The floor board structure is such that a housing recess 6 formed in the rear of a rear seat 2 is enclosed by a floor board 8, wherein the floor board 8 includes a body 33 and a seat joint 35 connected in a bendable manner to the body 33, while the seat joint 35 is characteristically kept erected with respect to the body 33 and connected to the back of the rear seat 8. The back face of the rear seat 2 has one end of a cover sheet 21 connected thereto, while the seat joint 35 is covered with the cover sheet 21.