To provide a chair for easily standing up and sitting down and to provide a vehicle mounting this chair in the state of enabling a person of deteriorated physical strength to use.

The center part 1 of the upper face of the seat of the chair is foldedly curved or bendingly raised symmetrically by electric power. The front part 2 of the upper surface of the seat is connected with a rotary joint R1 capable of turning movement in a surface vertical to a front leg part 3. The rear part 2 of the upper surface of the seat is connected with a rotary joint R2 capable of turning movement in a surface vertical to a rear leg part 5 and a back rest part 6 in one body. A front/rear leg connecting member 7 at a lower part can be turn-moved in a face vertical to one of the leg 3 and the leg 5. It is desirable to mount this chair and to select with button a linked program of arm operation, backrest part inclining operation and the height change of the seat from in plural programs.