A vehicle seat includes: a seat back frame that is provided with a pair of side frame portions that are located on both left and right sides in the seat transverse direction; an outer-side load transmitting block that is located further to an outer side in the transverse direction of the seat back frame than the side frame portion of the seat back frame, and that transmits an impact load that is input from a side of the vehicle body to the seat back frame; a protruding portion that protrudes from a side surface of the side frame portion on the outer side in the transverse direction of the seat back frame towards the outer side in the transverse direction of the seat back frame; a side airbag apparatus that is located on a front surface of the protruding portion; and an engaging portion that is formed in the outer-side load transmitting block, and that receives the protruding portion. The protruding portion is formed in a box shape that has a supporting surface on a surface thereof that faces the side airbag apparatus.
