SEAT FRAME

To reduce the weight of a cross member bridged between right and left sides of a seat frame. A seat frame includes an upper frame forming an upper portion of a seat back frame, and a cross member bridged at the upper frame. The cross member includes right and left end portions in a seat width direction, the right and left end portions being fixed to the upper frame; and a first recessed portion that is recessed upward or downward and provided between the right and left end portions. The first recessed portion is provided at a center portion of the cross member in the seat width direction.