A rotation seat for a vehicle, the rotation seat comprising: a base plate fixed on a body of the vehicle; a rotating plate rotatably connected to the base plate through a first shaft; and a seat fixed on the rotating plate, the seat being rotatable with the rotating plate to a forward driving position and an operator's exiting position, wherein the base plate includes a guide slot, the guide slot including: a first slot formed in the shape of an arc centered about the first shaft; and a second slot having a first end connecting to the first slot and a second end, the second slot being formed in the shape of a curve so as to make the second end approach the first shaft; the rotating plate includes a nail member and a biasing unit for urging the nail member in the direction away from the first shaft, and the nail member is rotatable with the rotating plate and is displaceable in relation to the first shaft and is guided by the guide slot so as to regulate rotation of the rotating plate, the second slot guides the nail member when the seat is rotated between the forward driving position and the operator's exiting position, and the biasing unit exerts a force on a wall forming the second slot through the nail member so as to make the rotating plate rotate from the operator's exiting position to the forward driving position, and wherein the guide slot further comprises a first recess extended in the direction away from the first shaft, and the rotating plate is locked at the forward driving position where the nail member is engaged in the first recess. a base plate fixed on a body of the vehicle; a rotating plate rotatably connected to the base plate through a first shaft; and a seat fixed on the rotating plate, the seat being rotatable with the rotating plate to a forward driving position and an operator's exiting position, wherein the base plate includes a guide slot, the guide slot including: a first slot formed in the shape of an arc centered about the first shaft; and a second slot having a first end connecting to the first slot and a second end, the second slot being formed in the shape of a curve so as to make the second end approach the first shaft; the rotating plate includes a nail member and a biasing unit for urging the nail member in the direction away from the first shaft, and the nail member is rotatable with the rotating plate and is displaceable in relation to the first shaft and is guided by the guide slot so as to regulate rotation of the rotating plate, the second slot guides the nail member when the seat is rotated between the forward driving position and the operator's exiting position, and the biasing unit exerts a force on a wall forming the second slot through the nail member so as to make the rotating plate rotate from the operator's exiting position to the forward driving position, and wherein the guide slot further comprises a first recess extended in the direction away from the first shaft, and the rotating plate is locked at the forward driving position where the nail member is engaged in the first recess. a first slot formed in the shape of an arc centered about the first shaft; and a second slot having a first end connecting to the first slot and a second end, the second slot being formed in the shape of a curve so as to make the second end approach the first shaft; the rotating plate includes a nail member and a biasing unit for urging the nail member in the direction away from the first shaft, and the nail member is rotatable with the rotating plate and is displaceable in relation to the first shaft and is guided by the guide slot so as to regulate rotation of the rotating plate, the second slot guides the nail member when the seat is rotated between the forward driving position and the operator's exiting position, and the biasing unit exerts a force on a wall forming the second slot through the nail member so as to make the rotating plate rotate from the operator's exiting position to the forward driving position, and wherein the guide slot further comprises a first recess extended in the direction away from the first shaft, and the rotating plate is locked at the forward driving position where the nail member is engaged in the first recess.