A headrest for vehicle seat includes: a generally inverted-U-shaped frame having a pair of headrest stays defined therein; and an impact absorption bar fixedly connected between those two headrest stays. The impact absorption bar is located in a predetermined spaced relation with an upper horizontal frame portion of the generally inverted-U-shaped frame. When a rear-end collision or the like occurs, a head of seat occupant is stably received by those impact absorption bar and upper horizontal frame portion, while the impact absorption bar being readily deformed by backward excessive great load applied thereto from the seat occupant's head to thereby absorb and reduce a corresponding impact energy to be imparted to the head.