Proposed is a folding seat that is capable of being folding to various positions by controlling a lever and the folding seat is capable of improving utilization of space around the folding seat. According to an embodiment of the present disclosure, the folding seat includes: a seat frame; a seat back frame cross-arranged in back of the seat frame, the seat back frame having a first side rotatably coupled to the seat frame; and a locking portion coupled at a first side thereof to the seat back frame and rotatably coupled at a second side thereof to the seat frame at a position between the seat frame and the seat back frame, wherein the locking portion is configured to be inserted into a rear portion of the seat frame or to be separated from the seat frame according to an operation thereof.