To provide a front sheet structure for vehicles that can block and open a walk-through aisle, and can block the walk-through aisle without matching a longitudinal sliding position and the reclining angle of a seat back in a driver's seat and a passenger's seat.

The front sheet structure comprises a first arm rest 4a, where an arm rest 4 is rotatably supported by the sheet back 12 via a support shaft 5; and a second arm rest 4b that is provided via hinges 6, 6 in a state, where the second arm rest 4b can be changed to a folded state in which the rest 4b is overlapped to the upper surface to the first arm rest 4a and in a state, where the arm rest 4b can be developed being inverted nearly by 180 degrees in the direction of car width. The front sheet structure has width for nearly blocking the gap between both the sheet backs 12, 22 in the driver's seat 1 and the passenger's seat 2 when the second arm rest 4b is set to a developed state, and achieves the passing of the walk-through aisle 3 formed between the driver's seat 1 and the passenger's seat 2 when folded.