To provide a longitudinally foldable chair with a storable side table in comparison with a conventional one in which a side-table is fitted to a chair to be developed laterally.

In the longitudinally foldable chair, a foldable side table mechanism 6 comprised of both a holding member 61 mounted in such a way as to be axially rotatable and a top plate 60 in a horizontal cantilever shape pivoted and held at the holding member 61 is arranged in a mid point of a leg feet 21v, which is a raised rod of a front leg frame body 21. Or a folding side table mechanism 7 is comprised of both a holding member 71 mounted and fixed to a mid point of the leg feet 21v, which is a raised rod of the front leg frame body 21 and a top plate 70 pivoted in such a way as to be horizontally rotatable and rotatable downward from an approximately horizontal direction at the holding member 71 via a hinge part 70a. A supporting member 8 is arranged between the top plates 60 and 70 and holding members 61 and 71.