PROBLEM TO BE SOLVED: To provide a chair capable of facilitating standing up from a sitting posture.SOLUTION: A chair 1 includes a chair body 2 and a base member 3. The chair body 2 includes a seat part 21 and a pair of right and left support members 22. The lower end surface of each support member 22 includes: a rear lower end surface 25a linearly extending in a horizontal direction a front lower end surface 25b linearly extending with an inclination forward and upward and a curved surface 25c positioned between the rear lower end surface 25a and the front lower end surface 25b. The chair body 2 is configured to be movable between a normal use state where the rear lower end surface 25a is abutted onto a support surface 31 of the base member 3 and a standing-up use state where the front lower end surface 32b is abutted onto the support surface 31 and also the seat part 21 is inclined forward and downward. When the chair body 2 is shifted from the normal use state to the standing-up use state, the curved surface 25c is brought into rolling contact with the support surface 31 and also the curvature center position of the curved surface 25c is horizontally moved by only a predetermined distance L.
