Abstract: An apparatus for turning up and down seats for a telescopic seating system includes as essential components a foot on which a single seat is fixedly mounted, a base frame having a support shaft inserted therethrough in the transverse direction so as to allow the foot to be turned up and down about the support shaft, a center shaft extending through the base frame in parallel with the support shaft and including an extension outside of the housing, a guide arm turnably mounted on the extension of the center shaft, a pair of first coil springs mounted on the support shaft within the interior of the base frame so as to allow the foot to be normally biased in the turning-up direction, a second coil spring mounted on the extension of the center shaft so as to allow the guide arm to be normally turnably biased in the forward direction, and a pair of tongue-shaped projections fixedly mounted on the center shaft within the interior of the base frame, a link plate bridged between a front shaft on the foot and a rear s