A tibia pad has: a right foot placement portion having a right side horizontal portion formed horizontally and on which a passenger's right heel is placed, and a right side inclined portion formed at a vehicle front side of this right side horizontal portion and inclined with respect to a vehicle longitudinal direction to head toward a vehicle upper side while heading toward a vehicle front side; a pair of groove portions formed, at least in a bottom surface of the right side horizontal portion at the right foot placement portion, to extend along the vehicle longitudinal direction and to lined-up in a vehicle transverse direction; and a step portion formed at a transition portion between the right side horizontal and the right side inclined portions, and positioned between a rear and a front side ribs are formed at the right side horizontal and the right side inclined portions, respectively.