A vehicle seat comprises a rectangular-shaped seat back frame having right and left side frames; a headrest for supporting a head of a seat occupant that is installed within the vehicle seat; a rear-end collision detector mounted to the seat back frame at a position behind the seat occupant, wherein the rear-end collision detector detects rearward movement of the seat occupant and moves rearward; a link member that supports the rear-end collision detector with the seat back frame therethrough; and a biasing member that biases the link member; wherein: the rear-end collision detector acts such that the rearward movement of the rear-end collision detector reduces a distance between a head of the seat occupant and the headrest, and a lower end portion of the biasing member is coupled to a rear portion of the side frame and disposed posterior to the rear-end collision detector.