PURPOSE: To enable the leg of a dental chair to be temporarily stopped when it is raised from horizontal to vertical position, when the rising motion of the chair leg is obstructed as the operator's foot, etc., gets caught in the chair.

CONSTITUTION: A dental chair, which has a chair back 2 and a chair leg 3 located respectively in front of and behind a chair seat 1 mounted on a chair lift 4, with the chair back 2 freely raised and lowered by operation of a driving source 4', is provided with a long-size rod 2e having one end pivotally secured to the end of the lower portion of the back rest 2 which is slightly spaced from the rotating shaft of the end of the chair back 2 and the other end pivotally attached near the root of the chair leg 3. The long-size rod 2e has a connecting portion comprising a cylinder portion 11 and a rod portion 12 slidably fitted into the cylinder portion 11.