To provide a bathtub lid which allows mold to hardly grow, reduces the whole height in a folding state as much as possible, and is compactly packed.

Multiple hard synthetic resin-made hollow plate-like bodies 2, each of which has a clogging cap at the both ends, are connected in parallel via soft synthetic resin-made thin plate-like connection pieces 10, 11. The connection of the upper end edges of the adjacent hollow plate-like bodies 2, 2 and the connection of the lower end edges are alternately performed, and the upper surfaces or lower surfaces of the hollow plate-like bodies 2, 2 are superposed when folded. A plurality of lines of slip stoppers 4 arranged on the lower surfaces of the hollow plate-like bodies 2 are arranged at positions so as not to be superposed on each other with the slip stoppers 4 of the adjacent hollow plate-like bodies 2 when the hollow plate-like bodies 2 are superposed. The clogging caps are formed to have a largeness for allowing the end surfaces of the adjacent clogging caps to abut on each other in the development state of the bathtub lid.