PURPOSE: To provide a reclining mechanism which is made smaller, has a good appearance and safety by a method wherein the rotating center of a pole is arranged at an upper part of a lower arm, and a tooth part which can be engaged and disengaged with the tooth part of a ratchet is formed at an intermediate part, and at a rotating end part, a cancel part which comes into contact with the tooth part of the ratchet is formed.

CONSTITUTION: The rotating base end part of a pole 38 is attached to an upper part of a lower arm 31, and the pole 38 is guided to a cam hole 42 by a handle 43, and the engagement with a tooth part 35a of a ratchet 35 is released. Also, when an upper arm 33 is tilted, and the force of the handle 43 is released, a tooth part 38a of the pole 38 is engaged with the tooth part 35a of the ratchet 35 again by a tension spring 50, and locked. Also, when the tooth part 38a of the pole 38 and the tooth part 35a of the ratchet 35 are disengaged by the handle 43, the upper arm 33 tilts forward. At this time, a cancel part 38b of the pole 38 comes into contact with the tooth part 35a of the ratchet 35 to unlock it, and the upper arm 33 is put under a forward tilted condition while being tiltable backward.