AUTOMOBILE FLOOR STRUCTURE

To achieve efficient and proper transmission of an impact load from a floor frame on one side of a vehicle body to a floor frame on the other side to thereby protect a battery unit from damage, an automotive floor structure comprises: a first cross member upper (22) extending in a lateral direction of the vehicle body and having ends attached to left and right side sills (10), respectively; and a first cross member lower (24) extending in the lateral direction below a front floor panel (12) at a position under the first cross member upper (22), and having ends secured to the left and right floor frames (14), respectively, wherein the first cross member upper (22) and the first cross member lower (24) vertically sandwich the battery unit (50) therebetween.